1. In the chemical formula for ammonia, NH3, what does the subscript 3 represent? (a) the number of ammonia molecules that will bond together (b) the number of nitrogen atoms in each molecule of ammonia (c) the number of nitrogen and hydrogen atoms in each molecule of ammonia (d) The number of hydrogen atoms in each molecule of ammonia 2. The diagram above shows a block from the periodic table. The number six represents the following consumers eats only producers?
(a) atomic mass of the element carbon (b) atomic number of the element carbon (c) number of neutrons in the element carbon (d) number of valence electrons in the element carbon 3. Insulation materials reduce heat loss because they (a) promote convection (b) block out the sun (c) reduce evaporation (c) are poor conductors In the food web shown, which of the 5.
(a) Mouse (b) Owl (c) Fox (d) Hawk Which system shows a transformation from chemical to electrical and light energy? (a) A display of fireworks in the night sky. (b) An avalanche rolls down a steep mountain (c) A car battery causes the headlights to shine (d) A candle burns and lights up the room 6. This experiment was set up to test the
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hypothesis that plants grow faster in green light. The same amount of water and fertilizer were added to each pot. Which of these would improve the experiment?
Both light bulbs are lit in the circuit above. In order to turn off both lights, a switch must be installed in the circuit at the place marked
(a) 4 (c) 2 9.
(b) 1 (d) 3
Calcium metal (Ca) can be produced by passing an electric current through molten calcium chloride (CaCl2). Chlorine gas (Cl2) is also formed. What is the balanced equation for this reaction? (a) CaCl2 ® Ca+Cl2 (b) 2 C aC l ® C a + 2 C l (c) CaCl2 -H2O ® Ca+ClH+O
(a) Use the same kind of plant in all trials (b) Add more types of plants (c) Use green lights for all three plants (d) Use different pots...