Which statement about the energy of a phase change is true?
a. melting is an endothermic change, because ice releases energy to its surroundings as it melts.
b. melting is an endothermic change, because ice absorbs energy from its surroundings as it melts.
c. melting is an exothermic change, because ice absorbs energy from its surroundings as it melts.
d. melting is an exothermic change, because ice releases energy to its surroundings as it melts.

What is the chemical name of the compound na2co3? use the list of polyatomic ions and the periodic table to you answer. a. sodium carbon oxide b. sodium carbonate c. sodium(ll) carbonate d. sodium oxalate

The molality of calcium chloride (cacl2) in an aqueous solution is 2.46 m. what is mole fraction of the solute?

Which statements are true concerning mineral formation? check all that apply. the slower the cooling, the larger the crystals. the faster the cooling, the smaller the crystals. crystals formed from magma are smaller than crystals formed from lava. minerals can only form in solutions when the solution is heated deep underground. when a solution cools, elements and compounds leave the solution and crystallize as minerals. minerals formed from hot water solutions can form narrow channels in the surrounding rock.