How many grams of Na2SO4, (molar mass =142.0 g/mol) are there in 15 mL of 0.50 m Na2SO4 solution?

Yes, endothermic means it turns cold. and some chemical changes include change of tempature.

The independent variable is the type of music.the dependent variable is the pulse rate.the intervening variable is the age of the subject.if the mother does not like rock, her pulse is likely to not increase.the same might be true for the sister.the friend may like rap and gets excited.to establish cause/effect relationship, all of the subjects must be consistent.hope i .

It would be true sodium reacts with water in a violent way