First, we have to get:
1- The heat required to increase T of ice from -50 to 0 °C:
according to q formula:
q1 = m*C*ΔT
when m is the mass of ice = mol * molar mass
= 1 mol * 18 mol/g
= 18 g
and C is the specific heat capacity of ice = 2.09 J/g-K
and ΔT change in temperature = 0- (-50) = 50°C
by substitution:
∴q1 = 18 g * 2.09 J/g-K *50°C
= 1881 J = 1.881 KJ
2- the heat required to melt this mass of ice is :
q2 = n*ΔHfus
when n is the number of moles of ice = 1 mol
and ΔHfus = 6.01 KJ/mol
by substitution:
q2 = 1 mol * 6.01 KJ/mol
= 6.01 KJ
3- the heat required to increase the water temperature from 0°C to 60 °C is:
q3 = m*C*ΔT
when m is the mass of water = 18 g
C is the specific heat capacity of water = 4.18 J/g-K
ΔT is the change of Temperature of water = 60°C - 0°C = 60°C
by substitution:
∴q3 = 18 g * 4.18 J/g-K * 60°C
= 4514 J = 4.514 KJ
∴the total change of enthalpy = q1+q2+q3
= 1.881 KJ +6.01 KJ + 4.514 KJ
= 12.405 KJ
Answer:
The top layer is the Aqueous layer, and the benzoic acid is contained in the non-aqueous layer/oil phase.
Explanation:
A separating funnel is a very important piece of laboratory glassware that is used to separate the components of liquid-liquid mixtures which are immiscible. This technique is used in the extraction of the components of mixtures.
The liquids separate into two phases. The separation is based on the differences in the liquids' densities, where the denser liquid settles below and the lower density liquid stays afloat. Liquids used for this kind of separation are usually different liquids, one is the aqueous layer and the other, a non-aqueous layer.
Partition coefficient or distribution coefficient is defined as the ratio of the concentrations of a compound in two immiscible solvents at equilibrium.
Organic solvents (except halogenated organic compounds) with densities greater than that of water i.e 1g/mL ( usually called the oil phase) settle at the bottom of the aqueous phase.
Benzoic acid. will settle at the bottom layer ( i.e the lower phase).
Answer:
Correct answer is b) convex mirror
Explanation:
A convex mirror, which bulges outward, reflects at a wider angle near its edges than at its center, creating a slightly distorted image that's smaller than actual size. Convex mirrors have many uses. The smaller size of the images means that you can see more with these surfaces, hence their use in safety mirrors.
Answer:
76.5g KCl/74.55 grams per mole Kcl = x
molality= x/.085 kg H2O
Explanation:
well remember molality is moles of solute/kilograms of solvent. So it's the moles of KCl over 85 g of h20 converted into kg. if this makes sense.
