(Please help me and thanks for your helpfulness) An unknown substance with a mass of 100 grams absorbs 1000J while undergoing a temperature increase of 15°C. What is the specific heat of the substance?

Mv^2 is a conserved quantity so v goes as sqrt(1/m) heavier is slower 64/4 = 16 sqrt(16) = 4

If each of the reactants have 2 elements it is usually double displacement. when there is double displacement, if one reactant has hydrogen then it can be acid base. if one reactant has 2 and one has 1, than it is usually single displacement. if there is only one reactant it is decomposition. if there are two reactants that each have one element it is synthesis. if one of the reactants is 02 it can be combustion and the products has to include h20 and c02.