1) Chemical reactions produce new substances
Ans (d)
2) The symbol, Δ in a chemical reaction means that heat of supplied to the reaction.
Ans (a)
3) A skeleton equations does not show the reaction stoichiometry, i.e. the relative amounts of reactants and products.
Ans (d)
so basically a atom type contains the same number of protons. Chemical bonds put elements together to form more complex molecules called compounds. A compound consists of two or more types of elements held together by covalent or ionic bonds. Elements can't be divided into smaller units not using large amounts of energy.
hope this helped ur boi- Johnny Joestar