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Science reviewer for biology and physical sciences let examiness

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Science reviewer for teachers who are going to take the PRC LET or BLEPT examination. this reviewer covers topics ranging from different chapters and different subjects.

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Science reviewer for biology and physical sciences let examiness

  1. 1. SCIENCE REVIEWER (covers the basics on all field of sciences except social sci.) (extracted by http://elio.p4o.net)(http://www.jokwasit.blogspot.com) What is the sun? -Star- What is the hottest planet in the solar system? -Venus- What planet is closest to the sun? -Mercury- What is the mutual attraction between all masses in the universe called? -Gravity- What is the earth's primary source of energy? -Sun- What is the biggest planet in our solar system? -Jupiter- What is the biggest organ in the human body? -Skin- What galaxy is the earth located in? -Milky Way- What is the first name of the scientist who gave us Newton's Laws of Motion? -Issac- How many lobes does a human brain have? -4- What is the largest muscle in the human body? -Gluteus Maximus- Which of these is the largest bone in the human body? -Femur- How many lungs are in a human body? -2- What lives in a Formicarium? -Ants- Who said "nature abhors a vacuum?" -Galileo- How many atoms are there in a molecule of water? -3- How many wisdom teeth does the average adult have? -4- How many millimeters are there in one inch? -25.4- What is removed during an appendectomy? -Appendix- What is classified by the A B O system? -Blood- 1
  2. 2. What is the chemical symbol for chromium? -Cr- What does a joule unit measure? -Energy- According to Newton, mass times acceleration is equal to what? -Force- What does a hertz unit measure? -Frequency- If you had rubella what would you have caught? -German measles- Which will not rust? -Gold- Alopecia describes a person with a lack of what? -Hair- Where in the body is the patella? -Knee- What is the chemical symbol for sodium? -Na- Which is the most common gas in the atmosphere? -Nitrogen- What is the most common blood type in humans? -O- What is not a primary color? -Orange- What do botanists study? -Plants- K is the chemical symbol for which element? -Potassium- What plant does the Colorado beetle attack? -Potato- What does a pascal unit measure? -Pressure- Which plant gives absynthe its hallucinogenic properties? -wormwood- Which temperature has the same value in degrees in both Celsius and Fahrenheit? --40- How many moons does Venus have? -0- How many moons does Saturn have? -62- About how many miles must one walk in order to burn off a pound of fat? -34- 2
  3. 3. How many elements from the periodic table occur naturally on earth? -94- How many liters are there in a barrel of oil? -159- What are lanthanides? -A block of elements in the periodic table- What can you see with Kirlian photography? -Aura- What is an Ishihara test used for? -Blindness- Which element is present in all organic compounds? -Carbon- What makes up 99.9% of the universe? -Dark energy- Where in your body would you find the rods and cones? -Eyes- Ir is the chemical symbol for which element? -Iridium- Mg is the chemical symbol for which element? -Magnesium- Mn is the chemical symbol for which element? -Manganese- What is the scientific name for laughing gas? -Nitrous oxide- What does a becquerel unit measure? -Radioactivity- The common cold is what kind of virus? -Rhino- What is the chemical symbol for antimony? -Sb- Which of the following is a theory in physics? -Schrodinger's Cat- What does an OLF unit measure? -Smell- What is the chemical symbol for tin? -Sn- On the Mohs scale, the hardest substance is diamond. What is the softest? -Talcum powder- What is the chemical symbol for titanium? -Ti- W is the chemical symbol for which element? -Tungsten- 3
  4. 4. Which planet in the solar system is closest in size to Earth? -Venus- Which plant gives absinthe its hallucinogenic properties? -wormwood- What kind of star is our sun? -Yellow Dwarf- How many inches to a cubit? -18- How many cubic feet are there in three cubic yards? -81- How many years is 1,000,000 hours? -114- In which year was the first black tulip cultivated? -1986- How many hairs does the average human head have? -100,000- What was the highest ever-recorded temperature in the Libyan desert? -136 degrees Fahrenheit- What is the speed of light? -186,272 miles per second (299,775,726 KM- How long does the light from the sun take to reach the earth? -8.5 minutes- What is the most common blood group in Europe? -A +- Which of these elements is the heaviest? -Caesium- How many earths would fit inside the sun? -about 1,000,000- Hypermetropic people are what? -Far sighted- Which planet has the tallest mountain? -Mars- What does the medical term dolent mean? -Pain- Which planet has the most eccentric orbit? -Pluto- Which planet has the most moons? -Saturn- Somatology is the study of what? -The body- A baby has 270 bones. How many bones does an adult have? -206- 4
  5. 5. A fetus acquires fingerprints at what age? -three months- About how many pints of blood are in the human body? -8 (3.79 L)- Bananas contain the natural chemical serotonin. How does it make a person feel? -happy- Genetic information is transferred from parent to daughter cells through what? -nucleus- How many chambers is the heart divided into? -4- How many chromosomes are in the human gene? -46- How many joints are in the human body? -230- How many pairs of chromosomes are in a human cell? -23- How many pairs of cranial nerves are there? -12- How much does the average human brain weigh? -1,400 grams- If you take a class in Mycology, what are you studying? -fungi- In what part of the body are the Betz cells found? -brain- Motor nerves carry nerve impulses to the muscles from what? -the senses- Sensory nerves carry nerve impulses from the senses to what? -brain- The death of an entire species is called what? -Extinction- The first patent for a tree was issued in 1932. What kind of tree was it? -a peach tree- The PH value of human blood is? -7.4- What absorbs most of the water in the alimentary tract? -the large intestine- What are leukocytes? -white blood cells- What are the oldest, most widely cultivated and used nuts in the world? -almonds- What bone is located in the collar region? -Clavicle- 5
  6. 6. What bone is located in the upper jaw? -Maxilla- What cell component is commonly used for personal identification? -DNA- What disease causes rapid and uncontrolled growth of abnormal cells? -Cancer- What disease causes yellowing of the eyes, skin and urine? -Jaundice- What do animal cells NOT contain? -cell walls- What filters the blood to excrete harmful substances in the form of urine? -Kidneys- What helps keep the human body cool? -Perspiration- What is 70% of the human body made of? -water- What is a fertilized human egg initially called? -zygote- What is a single piece of coiled DNA called? -Chromosome- What is Botany the study of? -Plants- What is glucose? -monosaccharide - What is the cell membrane made of? -phospholipids- What is the correct name for the nerve cell? -the neuron- What is the fastest-growing plant? -Bamboo- What is the green color in plants named? -Chlorophyll- What is the largest and longest bone in the human body? -the femur- What is the largest artery in the body? -Aorta- What is the largest organ in the human body? -skin- What is the most common element in the human body? -Oxygen- What is the most common human blood type? -O Positive- 6
  7. 7. What is the movement of organisms away from sunlight known as? -Negative phototaxis- What is the nerve from the eye to the brain? -optic- What is the periderm of a plant also known as? -the bark- What is the rarest blood group? -AB Negative- What is the scientific term for the production of light by living organisms? -Bioluminescence- What is the smallest bone in the body? -stirrup- What is the structure of the hindbrain? -Pons- What kind of plant is a mango? -flowering- What metal is present in chlorophyll? -Magnesium- What metal is present in hemoglobin? -Iron- What method is used to kill the bacteria in milk ? -Pasteurization- What part of the body produces bile? -liver- What part of the eye adjusts to focus more clearly? -the lens- What part of the human body cleans up to 50 gallons of blood every day? -the kidneys- What part of the human brain does alcohol affect? -Cerebellum- What prevents the entry of food into respiratory passages? -Epiglottis- What scientist created the first recombinant DNA molecules? -Paul Berg- What scientist showed that genetic material is a heat stable chemical? -Franklin Griffith- What type of proteins are collagen (fibre in bone and ttendon and other connective tissues) and elastin (elastic tissues)? -structural proteins- What type of tree bark is used to make Quinine(malaria theraphy)? -Cinchona- What was the first genetically engineered organism? 7
  8. 8. -Tobacco- What was the first animal to be successfully cloned? -Sheep- Where are fats, carbohydrates and proteins digested? -the small intestine- Where are villi not found? -in the colon- Where in the heart does the aorta originate from? -left ventricle- Where is the tympanic membrane found? -Ear- Where on the human body is the thickest skin located? -Palms or Soles- Which blood group is known as the 'Universal Donor' ? -Group O- Which blood group is known as the 'Universal Recipient' ? -Group AB- Which of these diseases is airborne? -Bronchitis- Arthritis Malaria Lung Cancer Which of these is a naked-seeded plant? -a sunflower- a cedar tree a guava a maple tree Which organ is the spleen located behind? -the stomach- Which organism is helpful in making the soil fertile ? -Earthworm- Which part of the respiratory tract is also known as the voice box? -Larynx- Pharnyx (passage of food) Who discovered Penicillin ? -Alexander Fleming- Who discovered the bacteria that causes Anthrax? -Robert Koch- Who discovered the vaccine for smallpox? -Edward Jenner- Who has more bones? -a baby (270)- Who has the longest recorded life span? -Freshwater Oyster- 8
  9. 9. Who introduced sterilization of surgical instruments ? -Joseph Lister- Chronic infection with hepatitis C virus will lead to what? -Liver cirrhosis- In the human body, the optic nerve sends signals from the eye to what? -Brain- In which process do plants bend toward light? -phototropism- Scurvy is caused by a deficiency of what? -Vitamin C (ascorbic acid)- The cells of human males have what two chromosomes? -One X and One Y- What is a more scientific term for "high blood pressure"? -hypertension- What is a prokaryotic cell missing? -nucleus- What is the pituitary gland attached to? -Brain- What molecule in the blood carries oxygen? -Hemoglobin- What part of the human body shares its name with that of a punctuation mark? -Colon- Where in the human body would you find your Adam's Apple? -Neck- Where is a human's appendix located? -right side- Where is undigested food stored? -large intestine- Which joint is most commonly affected by the first attack of gout? -big toe- Which term means "weakening of the bones"? -osteoperosis- Which is longer: the large or small intestine? -small- What name is given to the clear layer at the front of the eye? -cornea- How many electrons are in a Hydrogen atom? -1- If an atom has 13 electrons, how many shells will have electrons? -3 (spdf)- What is an example of a crystal lattice? -Diamond- 9
  10. 10. What is the symbol that stands for the speed of light in a vacuum? -c- How many states of matter are there? -5 (solid,liquid,gas,plasma)- What term is used to describe the phase change of a liquid to a gas? -boiling- What is the most common solvent on Earth? -water- What forces keep molecules together when the surrounding energy drops? -Attraction- What element is #1 on the periodic table of elements? -Hydrogen- Which of these is an inert gas (stable elements)? -Neon- How are Elements in the periodic table arranged by? -Atomic Number- What has the least energetic molecules? -solids- Which element is not found in the Earth's atmosphere? -Gold- What are rows in the periodic table called? -periods- What is the lightest halogen (from top-light- to bottom-heavy-)? -Fluorine- What is the name of the compound NaCl? -Sodium chloride- Where are halogens found on the periodic table? -right side (group 17)- Basic pieces of an atom. Neutron Electron Proton What do chemical reactions create and break down? -chemical bonds- Where will you usually find carbohydrates? -starches- What are the columns of the periodic tables called? -groups- What smaller pieces are proteins made of? -Amino Acids- What force pulls liquids towards the ground? -gravity- 10
  11. 11. What is the term for a reaction happening in several steps? -Reaction Mechanism- What is water when it is at room temperature? -liquid- Who came up with a periodic table that included all of the known elements? -Dmitri Mendeleev- What scientist is famous for his equilibrium principle? -Le Chatilier- What is a positively charged ion called? -Cation- When water is in a solid form, what is it called? -ice- Example of a temperature scale. Kelvin Fahrenheit Celsius The equilibrium constant can be changed when what changes? -Temperature- What are Purines and Pyrimidines types of? -Nucleotides (basic stucture unit of DNA & RNA)- What is the metabolic process that breaks down sugars to release energy? -Glycolysis- Phospholipids have what element in the compound? -Phosphorus - How many basic structures do proteins have as they are being synthesized? -4- What is the salt that absorbs water called? -Hygroscopic Salt- When burning charcoal, what gas is produced? -Carbon Dioxide (oxygen used to burn)- What is the conversion of water vapor to water on a cold glass known as? -condensation- What form is most of the pure, drinkable water of the earth in? -icebergs- What is a barometer used for measuring? -Atmospheric Pressure- What is it called when you add chlorine to water to kill microbes? -Chlorination- What is lemon juice? -acidic (less than 7, excess hydrogen)- Acids change a litmus paper from blue to what color? -red- 11
  12. 12. Make up Earth's atmosphere. Oxygen Carbon Dioxide Nitrogen Which gas is green in color? -chlorine- Which of these is necessary for a substance to burn? -Oxygen- What does the lead of a pencil mainly contain? -graphite- What is the chemical symbol for fluorine? -F- Cd is the symbol for what element? -cadmium- What causes the fizz in soft drinks? -carbon dioxide- What type of acid does milk have? -lactic- Allotrope (other form) of carbon. diamond charcoal graphite What is the chemical name of Vitamin C? -Ascorbic Acid- Found in baking powder. Tartaric Acid Used in glass,paper,welding and preservative. Boric Acid Used as bleach and rust remover. Oxalic What is the combination of any substance with oxygen known as? -oxidation- What are rocks that are rich in metals known as? -ores- What gas is evolved when dilute sulphuric acid is added to Zinc? -Hydrogen- Who discovered anode rays? -E. Goldstein- With which metal does oxygen combine to form rust? -iron- What is the opposite of acids? -bases- 12
  13. 13. Which metal is extracted from the ore 'bauxite'? -aluminum- What is the minimum number of elements needed to form a compound? -2- Co is the symbol for what element? -cobalt- What appears when elements bond? -compounds- What was the particle discovered in the anode ray experiments? -proton (+)- How many elements is salt made of? -2 (NaCl)- How many elements is sugar made of? -3- An element is determined by the number of what? -protons (atomic number)- What holds the elements? -Periodic Table- What are protons, neutrons, and electrons the three basic components of? -atoms- By changing the number of electrons on an atom, you produce a different _____. -ion (atom that lost or gained electrons)- What English chemist and physicist discovered hydrogen? -Henry Cavendish- Who is known as the father of chemistry? -Robert Boyle- Changing the number of neutrons of an atom changes its _____. -isotope (same atomic # but dif. neutron)- What is the element of the symbol Sn? -tin- What are substances that control the rates of chemical reactions? -catalysts- What is matter that does not enter chemical reactions described as? -inert- What is the name for anisole? -methoxy benzene- Which is strong acid? -HBr (bottom right)- HCL HCA HF Which one is a saturated compound? -propane- 13
  14. 14. What is the chemical formula for benzene? -C6H6- Who proposed the theory of relativity? -Albert Einstein- What is the main element of organic compounds? -C- Which of these is the most acidic in nature? -ethyne- ethane methane lime What is a substance that dissolves other materials known as? -solvent- What functional group is present in aniline(dye,plastic,med)? -amine- How many of the currently known elements occur naturally? -88- At room temperature, what is the only metal that is in liquid form? -mercury- What is the fourth-most abundant element in the universe in terms of mass? -carbon- Which is the first alkene member? -ethene- What is the element symbol for tungsten? -W- According to the periodic table, what is calcium classified as? -alkaline earth metal- In the periodic table of elements, what element has the symbol "Na"? -Sodium- In the periodic table of elements, what is Krypton classified as? -Noble gas/inert- Sea water typically freezes at a temperature ____ than fresh water. -lower- What color does copper turn as it ages? -Green- What is the chemical symbol for gold? -Au- What is the chemical symbol for potassium? -K- What is the chemical symbol for the element copper? -Cu- What is the most abundant element in the earth's crust? -oxygen- 14
  15. 15. What is the most plentiful metal in the earth's crust? -Aluminum- What is the scientific symbol for Zinc? -Zn- What is the scientific symbol of Mercury? -Hg- What name is given to a solution which is more dilute in comparison to another? -Hypotonic- What scale indicates whether a substance is an acid, a base, or neutral? -pH- What temperature equals 0 degrees celcius? -32 degrees fahrenheit- Which category of elements have the greatest number of elements? -Metals- Which European country has two elements in the periodic table named after it? -France- The nucleus of an atom consists of _____. -Protons and Neutrons- What is a transformation of some substances into one or more other substances? -chemical reaction- What temperature is the zero point on the absolute temperature scale (Kelvin)? --273 degrees celsius- Around 35% of dinosaurs were omnivores, which meant they ate what? -a variety of food- What are scientists who study dinosaurs called? -Paleontologists- What type of lens does a magnifying glass have? -convex lens- What is it called when light bends as it enters a different medium? -refraction- What unit is electric resistance typically measured in? -ohms- If a 220-pound (99.7kg) person from Earth went to Mars, about how much would they weigh? -84 lbs. (38)- How is energy from wood measured? -by calories- At approximately what speed does sound travel at? -757 miles per hour (1218.27 km/h)- What planet spins in the opposite direction to Earth? -Venus- 15
  16. 16. What year did Albert Einstein win the Nobel Peace Prize for his work in Physics? -1921- Who invented the lightening rod? -Benjamin Franklin- What are caused by the Earth's rotation and the gravity of the Moon and Sun? -tides- What are large groups of wind turbines called? -wind farms- How long does light take to get from the Earth to the Moon? -1.255 seconds- Galileo Galilei was born in 1564. What country was he born in? -Italy- What is the largest planet in our solar system? -Jupiter- What animal can hear at a higher frequency then humans? -dogs- Metals expand when they are heated. What do they do when cooled? -contract- What is the wire that is in an electric light bulb known as? -filament- Who is the Hubble Space Telescope named after? -Edwin Hubble- What unit is electric current typically measured in? -ampere- What is the most recognized model of how the universe began? -The Big Bang- What is the only planet in our solar system that rolls on its side like a barrel? -Uranus- How is potential electric energy measured? -in volts- Which one of these did Galileo Galilei invent? -thermometer- What country was the physicist James Maxwell born in? -Scotland- On Earth, what is the biggest source of energy for producing electricity? -coal- Where was Isaac Newton born? -England- What can't sound travel through? -a vacuum- Albert Einstein was born in what country? 16
  17. 17. -Germany- How does heat from the sun get to the Earth? -radiation- What word describes anything that is occupying space? -matter- What are substances that don't radiate heat know as? -insulators- Who was the first to say that the Earth revolves around the sun? -Nicolaus Copernicus- Who won the Nobel Peace Prize for discovering radon and polonium? -Marie Curie- What's short for "light amplification by stimulated emission of radiation"? -a laser- According to legend, what kind of tree was Isaac Newton sitting under when he realized gravity? -apple- In what form does energy travel between cell phones? -radio waves- What was found on Mars that led some scientists to believe that there was once life there? -water- What is the scientific study of sound waves known as? -acoustics- What was measured in the famous Michelson-Morley experiment of 1879? -speed of light- Which of the quantities are always conserved in a closed system? -energy- How many colors are there in the spectrum when white light is separated? -7- What did Dennis Gabor invent in 1947, that won him a Nobel prize in 1971? -holograms- Who coined the term "black hole"? -John Wheeler- When a spring is released, what is its potential energy converted to? -kinetic energy- What is the lightest element? -hydrogen (top left)- What is the heaviest natural element? -uranium- What force opposes the relative motion of two bodies that are in contact? -friction- What is the SI unit for mass? -kilogram- 17
  18. 18. Of the three states of matter, which has neither definite volume or shape? -gas- What is the SI unit for the amount of substance? -mole- What is a substance which consists of atoms that are alike called? -an element- Which one of these has the lowest density? -cork- water glass milk What is the unit for illumination? -lux- What is the SI unit for time? -a second- Which of these has the highest density? -tungsten- mercury lead What is the rate of change of displacement called? -velocity- What is pressure defined as? -force/area- What instrument is used for measuring atmospheric pressure? -a Barometer- What is the SI unit of pressure? -Pascal- What is heat a form of? -energy- What is the name of the magnetic iron ore once used as a primitive compass? -Lodestone- What are the only materials that can be influenced by a magnet? -magnetic materials- What are electrons that easily move from one atom to another called? -free electrons- What is an atom that is deficient in electrons called? -a positive ion (cation)- What is the central core of an atom also referred to as? -nucleus- What are bodies that radiate light called? -luminous- What are materials that light cannot pass through called? -opaque- 18
  19. 19. What is the SI unit of frequency? -Hertz- What is the time in which a vibrating body completes one vibration called? -time period- What is the distance between two consecutive crests of a wave called? -wavelength- What is the lower limit of frequency that can be heard by the average human? -20 Hz- What keeps the pressure in the middle ear the same as the outside air pressure? -Eustachian tube- Heat capacity = Specific heat capacity multiplied by _____. -mass- What is the freezing point of water? -273 K- What is the heat gained or lost by a body resulting in a change in temperature? -sensible heat- What is the SI unit of momentum? -N*s ((kg*m/s2)*s)- What is the gravitational force acting on an object called? -weight- The resistance offered by an object to an applied force is referred to as? -inertia- Work is done when what moves through a distance? -force- What was the thermometric fluid used by Galileo in his thermometer? -air - What is ultraviolet light a form of? -radiation- Which of the following substances has the highest specific heat capacity? -water- copper iron silver About how many miles can light travel in one year? (a light year) -5.88 trillion- 5.88 million 5.88 thousand 5.88 billion In the visible light spectrum what color appears between yellow and blue? -Green (ROYGBV)- In what year was Isaac Newton born? -1642- What are individual particles of light called? -Photons- 19
  20. 20. What color are the hottest stars? -blue-white- What does an anemometer measure? -wind velocity- What is a dying star that explodes into brilliant light? -Supernova- What is another name for a black hole's gravitational border? -Event Horizon- What is the effect caused by light bending around obstructions in an optical system. -Diffraction- Crick and Watson discovered the helical structure of what in 1953? -DNA- How many elements are on the basic periodic table? -117- Which equipment is used to register the intensity of an earthquake? -Richter Scale- Deuterium and Tritium are isotopes of which gas? -Hydrogen- By subtracting 32, multiplying by 5 and dividing by 9, what conversion is made? -Fahrenheit to Centigrade- *celcius=(f-32)x(5/9) Which word means "a prolonged painful contraction of a muscle"? -cramp- Where is the friggia on the human body? -The interdistal area between the toes- Which of these elements has the lowest atomic number? -Technetium- Uranium Tellurium Radon Which is the largest joint in the human body? -Knee- Which scale is used to measure the hardness of metals? -Moh's Scale- What is the longest bone in the human body? -femur- How many pairs of chromosomes does the normal human have? -23- The red mineral Cinnabar is the chief source of what? -Mercury- Which rocks cover about three-fourths of the Earth's surface? -sedimentary- In what year did Stephen Hawking publish "A Brief History of Time"? 20
  21. 21. -1988- In what year did Albert Einstein publish the "General Theory of Relativity"? -1915- In what year did Heisenberg state his uncertainty principal? -1923- *position and momentum (energy and time) cannot be measured both at once. In what year was the neutron discovered? -1932- In what year did Charles Darwin publish "On The Origin of Species"? -1859- In what year did Sigmund Freud publish "The Interpretation of Dreams"? -1900- In what year was Penicillin first used to successfully treat a patient? -1943- In what year did Dolly the sheep become the first mammal to be cloned? -1996- About when was geometry developed in Egypt? -1500 BC- What kind of animals live in both water and on land? -amphibians- In humans, males have which chromosomes? -XY- In humans, females have which chromosomes? -XX- Which of these is not a phase of cell mitosis? -endophase- prophase metaphase telophase Who said "light may be shed on man and his origins"? -Charles Darwin- Atomic weight is determined primarily by the number of _____. -protons and neutrons- Most planets in our solar system are named after what? -Roman Gods- St. Elmo's fire is named after St. Erasmus of Formiae, the patron saint of _____. -sailors- What discovery was made by Marie Skodowska-Curie and Pierre Curie in 1898? -Radium- Which vitamin was discovered first, in 1913? -A- A perennial plant must have a life cycle of more than how many years? 21
  22. 22. -2- In what year was the first human heart transplant performed? -1967- In what year was the first "test tube baby" born in England? -1978- How many joints do humans have in their necks? -7- How many degrees, in Kelvin, is equal to minus 273.15 degrees celcius? -0- What is the more common name for a circumorbital hematoma? -black eye- In what year was the first kidney transplant? -1954- What is the more common name for nitrous oxide? -laughing gas- What was the name of the first cloned sheet in 1996? -Dolly- Ultraviolet radiation is absorbed by which layer of the stratosphere? -ozone- What is the main downward-growing root of a plant called? -taproot- What is the hardest substance in the human body? -tooth enamel- What unit is electric power typically measured in? -watts- *P=j*s(R*C) Objects with mass are attracted to each other. What is this known as? -gravity (universal law of gravitation--G=Gmm/r2)- How many electrons would a neutral halogen atom have in its outer orbital? -7 (to be stable use spdf with value 2,6,10,14 if the last spdf config has the upperscript of the spdfvalue 261014 then stable) - What letter represents the equilibrium constant? -K- What is water called when it's pure and free of any impurities? -distilled water- 22