Answer:
C) 1 and 3
Explanation:
A period in the periodic table is a row of chemical elements. All elements in a row have the same number of electron shells. ... Arranged this way, groups of elements in the same column have similar chemical and physical properties, reflecting the periodic law.
Answer:
The answer is B. Hope this helps! please give me brainliest!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! =)
Answer:
1.The substance(s) to the left of the arrow in a chemical equation are called reactants. A reactant is a substance that is present at the start of a chemical reaction. The substance(s) to the right of the arrow are called products . A product is a substance that is present at the end of a chemical reaction.The combustion of methane or octane is exothermic; it releases energy. CH4 + 2 O2 → CO2 + 2 H2O + energy The energies of the products are lower than the energiies of the reactants.
Explanation:
