12. Calculate the volume of a 0.45M solution containing 20 g of NaOH.

1.11L

Explanation:

To solve this problem, first, let us calculate the number of mole of NaOH as shown below:

Molar Mass of NaOH = 23 + 16 + 1 = 40g/mol

Mass of NaOH = 20g

Number of mole =?

Number of mole = Mass /Molar Mass

Number of mole of NaOH = 20/40 = 0.5mol

Now we can calculate the volume of the solution as follows:

Molarity = 0.45M

Mole = 0.5mole

Volume =?

Molarity = mole /Volume

Volume = mole /Molarity

Volume = 0.5/0.45

Volume = 1.11L

1.11L

Explanation:

Firstly calculate the molar mass of NaOH,40+16+1=40g/mol

Number of moles= molarity×volume

Number of moles=mass given/molar mass

Mass given=20g

Molar mass=40

Number of moles=20/40=0.5moles

Molarity=0.45M

Volume=number of moles/molarity

Volume=0.5/0.45

Volume=1.11L

answerlinnaeus;

weight of any object is given by

w = m*g

where m is mass of the object and g is the acceleration due to gravity.

for earth the value of g is 9.8 m/s^2 so

w=117.6 n m=12 g=?

117.6=12g => g=9.8 m/s^2

which is the force of gravity on earth.