First M stands for Molarity which is (moles of solute) / (Liters of solution). we also know that moles = (mass) / (molar mass). so we can form some equations here. We know:
Molarity (M) = moles (mol) / Liters (L)
moles (mol) = (mass) / (molar mass)
we can substitute the (mass) / (molar mass) for (moles) and get:
M = [(mass) / (molar mass)] / Liters
we can now isolate mass and get
M * Liters * molar mass = mass
now we need to find the molar mass of CaCl2 which is 110.98 g/mol
plug the values in and get
.350M * 6.5L * 110.98 g/mol = mass
mass = 252.4795g however the 6.5L has only 2 sig figs so i would say
mass CaCl2 = 2.5 * 10 ^2 g
The option that distinguishes a nuclear reaction from a chemical reaction is D. there is a change in the nucleus.
During a nuclear reaction, two light nuclei combine in order to create a new, heavier one which is different than those two original ones and has additional particles that it didn't have originally. This is what makes the difference between these two reactions.
Answer : The molecular formula of the compound will be, 
Explanation :
Empirical formula : It is the simplest form of the chemical formula which depicts the whole number of atoms of each element present in the compound.
Molecular formula : it is the chemical formula which depicts the actual number of atoms of each element present in the compound.
For determining the molecular formula, we need to determine the valency which is multiplied by each element to get the molecular formula.
The equation used to calculate the valency is :

As we are given that the empirical formula of a compound is
and the molar mass of compound is, 90.09 gram/mol.
The empirical mass of
= 1(12) + 2(1) + 1(16) = 30 g/eq


Molecular formula = 
Thus, the molecular formula of the compound will be, 
Future changes are expected to include a warmer atmosphere, a warmer and more acidic ocean, higher sea levels, and larger changes in precipitation patterns. The extent of future climate change depends on what we do now to reduce greenhouse gas emissions. The more we emit, the larger future changes will be
I believe it is A because a physical change is something that can be changed back to where a chemical change can not be such as burning something.