Answer the following question given this paragraph: Noble gases are the least reactive of all elements. That's because they have eight valence electrons, which fill their outer energy level. This is the most stable arrangement of electrons, so noble gases rarely react with other elements and form compounds. Q: What type of gases are the least reactive of all elements? Choices: - brave - humble - lucky - noble A:
noble

Answer the following question given this paragraph: A chemical reaction occurs when some substances change chemically to other substances. Chemical reactions are represented by chemical equations. Q: What occurs when some substances change chemically to other substances? Choices: - toxic reaction - spontaneous mutation - hormonal reaction - chemical reaction A:
chemical reaction

Answer the following question given this paragraph: Around 1850, a German doctor named Rudolf Virchow was observing living cells under a microscope. As he was watching, one of the cells happened to divide. Figure below shows a cell dividing, like the cell observed by Virchow. This was an "aha" moment for Virchow. He realized that living cells produce new cells by dividing. This was evidence that cells arise from other cells. Q: German doctor rudolf virchow first discovered what process when studying living cells under a microscope? Choices: - radiation - evolution - photosynthesis - cell division A:
cell division

Answer the following question given this paragraph: When zinc reacts with hydrochloric acid, the reaction bubbles vigorously as hydrogen gas is produced ( Figure below ). The production of a gas is also an indication that a chemical reaction may be occurring. Q: When zinc reacts with hydrochloric acid, the reaction bubbles vigorously as which type of gas is produced? Choices: - chlorine - oxygen - nitrogen - hydrogren A:
hydrogren