1. The molarity of a solution of 6.0 g of KCl in 80. mL of solution is

1.0 M of KCl

Explanation:

First off, we're given 6.0 g of KCl. From here, we just find the molar mass of KCl by adding the molar masses of each element in the compound. The molar mass for the potassium is 39 g/mol, and the chlorine is 34 g/mol (all found on periodic table). We add those to find the compounds molar mass, which turns out to be 73 grams/ mole.

From here, we need to convert grams to moles so we multiply the grams by the molar mass so that we cancel out grams and only leave behind moles ( 6.0 grams x  1 mole/73 grams ≈ 0.08 moles).

From here, we need to find the amount of liters in the solution, considering that the Molarity (M) is the same equation as mol/ Liter. To find this, we must convert similar units so that they work, in this case, we must convert milliliters to liters. We know that 1000 milliliters are equal to 1 liter, therefore like what we did with the molar mass and grams, we must cancel out milliliter so we only have liters ( 80 mL  x  1 L / 1000 mL= 0.08 L)

From here, we divide the moles by the liters in order to make the molarity. The reason why is because as said before, M is equal to mol/L  

(0.08 moles / 0.08 L = 1.0 M)

I hope this helped you and good luck with your semester in Chemistry!

  the   balanced   equation   for   reaction of   ca metal   with   o2 to   produce   cao   is as below

2 ca+ o2→ 2 cao2

  explanation

the reaction is   balanced     since the   number of atoms   in reactant side is   equal to   number of atoms   in   product side.   for   example   they   are 2   atom of   ca in   reactant   side   and   2   atoms of ca   in   the product side.

  the   process   is a   meet the   requirement   of   redox   reaction because :     calcium   is   oxidized   from   oxidation state 0   to 2+   while   oxygen   is reduced from   oxidation   state   0   to 2-