What is the molarity of 10.0 g of NaCl dissolved in water to make 100. mL?

= 1.7 M

Explanation:

Molecular mass of NaCl = ( 23+35.5 ) = 58.5g

58.5g of NaCl are weighed by 1 mole of NaCl

10.0g of NaCl will be weighed by ( 10÷58.5 )

= 0.17 moles of NaCl

100mL = ( 100÷1000)L = 0.1L

0.1L of a solution is occupied by 0.17 moles of NaCl

1L of solution will be occupied by [(1÷0.1)×0.17]

=1.7 M

  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-

2b2t

explanation:

2b2t