Part a
what is the mass of the water?
express your answer to two significant figures and include the appropriate units.

Answer

mass of 1 mole = 18g

mass of 1 mL = 1g

the unit used is gram

Explanation:

There are two ways to find mass of water:

1st way:

If we find Mass of water for one mole of water:

For this purpose we use mole formula as below

                          no. of moles = mass in grams / molar mass

if we find mass for one mole of water:

then

no. of moles of water = 1 mol

molar mass of water = H₂O = (1x2 +1x16) = 18 g/mol

mass of water = ?

Put the value in the mole formula

          no. of moles = mass in grams / molar mass . . . . . . . . . . . . (1)

by rearranging the formula (1)

            mass in grams = no. of moles x molar mass

            mass in grams = 1 mole x 18 g/mol

            mass in grams =  18 g

So for one mole of water the mass of water is 18 g and the unit for it is gram.

2nd way:

We can find mass of water by another way too

if we find the mass 1 mL of water

then the formula will be used is

                              D = m/v

where D is density

m is the mass

and v is the volume

So

density of water for 1 mL (D) = 1 g/ml

volume of water = 1 mL

mass of water = ?

By Rearranging density formula for mass

                                m = D/v (2)

put the values in equation 2

                                m= 1gmL⁻¹ / 1 mL

                                 m= 1g

So the mass of 1mL is 1g

hey there!

boiling point is the temperature at which the vapor pressure of the liquid equals atmospheric pressure. the vapor pressure of solvent molecules is decreased when a solute is added, so a higher temperature is required to increase the number of solvent molecules in the gas phase above the liquid.

at the freezing point, the vapor pressures of the solid and liquid are equal; a lower temperature is needed to reduce the number of solvent particles above the liquid.

hope this you

tobey