Statement 2 is correct.
solids moving into solution is a physical change as the core structure of the molecules remain the same. evaporation of water and crystallization of salt are both physical changes as well.
The water does not change it's H2O chemical makeup because salt was dissolved into it.
Answer: The issue of long-term effects of the Chernobyl disaster on civilians is very controversial. The number of people whose lives were affected by the disaster is sizable. Over 300,000 people were resettled because of the disaster; millions lived and continue to live in the contaminated area.
Explanation:
Some of the reactants or the products are in the gaseous phase.
The answer is 6.88.
Solution:
We can calculate for the percent composition of CaCl2 by mass by dividing the mass of the CaCl2 solute by the mass of the solution and then multiply by 100. The total mass of the resulting solution is the sum of the mass of CaCl2 solute and the mass of water solvent. Therefore, the percent composition of CaCl2 by mass is
% by mass = (mass of the solute / mass of the solution)*100
= mass of solute / (mass of the solute + mass of the solvent)*100
= (27.7 g CaCl2 / 27.7g + 375g) * 100
= 6.88
