Idont understand it 1.what is the boiling point of a solution of 675 grams of ethylene glycol (c2h6o2) in 2.50 liters of water?

102 °C

Explanation:

The boiling point elevation is computed as follows:

ΔT = k*m*i

where ΔT is the difference between the solution's boiling point and water's boiling point, k is a constant (0.51 °C*kg/mol for water), m is the molality of the solution, and i is the van't Hoff constant (equal to 1 for ethylene glycol  because is a covalent molecule and it doesn't dissociate).

Molar mass of ethylene glycol: 62.07 g/mol

Moles of ethylene glycol: mass / molar mass = 675/62.07 = 10.87 mol

Density of water: 1 kg/L

Mass of water: density * volume = 1*2.5 = 2.5 kg

Molality of the solution: moles of solute / kg of solvent = 10.87/2.5 = 4.348 mol/kg

Then:

ΔT = 0.51*4.348*1 = 2.217 °C

Boiling point of water: 100 °C

Then, the boiling point of the solution is 100 + 2.217 ≈ 102 °C

conduction is the transfer of thermal energy (heat in transfer) due to collisions between the molecules in the object. collisions between adjacent atoms and molecules transfer kinetic energy from the warmer to the cooler object. the objects must be in physical contact.

as given the equation is

2al + 6 hcl > 2 alcl3 + 3 h2(g)

as per equation two moles of aluminum reacts with six moles of hcl to give two moles of alcl3 and three moles of hydrogen gas

given: three moles of al are present and 7 moles of hcl

for three moles of aluminum nine moles of hcl will be required

however as 7 moles of hcl are present so the limiting reagent is hcl

hcl is going to decide the number of moles of product formed

when six moles of hcl are present = 3 moles of h2 are formed

when one mole of hcl is present == 3/6 mole sof h2 will be formed

when 7 moles of hcl are present = 3 x 7/ 6 moles of h2 will be formed = 3.5 moles of h2