A0.588 g sample of a nonvolatile, yellow crystalline solid dissolves in 11.5 g of benzene, producing a solution that freezes at 5.02 oc. find the molar mass of the yellow solid. the following may be useful: the freezing point of benzene is 5.51 oc and the freezing point depression constant, kf, is 4.90 oc/m.

The molar mass of the solid is 511.3 g/mol

Explanation:

Step 1: Data given

Mass of the sample = 0.588 grams

Mass of benzene = 11.5 grams

The solution freezes at 5.02 °C

The freezing point of benzene is 5.51 °C

The freezing point depression constant, kf = 4.90 °C/m

Step 2:  Determine the temperature change

Δt = 5.51 - 5.02 = 0.49°C

Step 3: Determine number of moles

Δt = i*Kf*m

⇒ with i = the number of dissolved particles the solute produces = 1

⇒ with Kf = the molal freezing point depression constant Kf = 4.90 °C*Kg/mol

⇒ with m =  the molality of the solute

0.49 °C = (1) (4.90 °C kg/mol) (x / 0.01150 kg)

x = 0.00115 mol

Step 4: Calculate molar mass

0.588 grams / 0.00115 mol = 511.3 g/mol

The molar mass of the solid is 511.3 g/mol

the only liquid elements at standard temperature and pressure are bromine (br) and mercury (hg). although, elements caesium (cs), rubidium (rb), francium (fr) and gallium (ga) become liquid at or just above room temperature.

explanation:

the law of conservation of mass states that in a chemical reaction, the total mass of reactants is equal to the total mass of products. because atoms are only rearranged in a chemical reaction, there must be the same number of sodium atoms and chlorine atoms in both the reactants and products