An SI base unit for measuring length would be meters.
Answer:
ΔU = −55.45 kJ
Explanation:
From first law of thermodynamics in chemistry, we have;
ΔU = Q + W
where;
ΔU is change in internal energy
Q is the net heat transfer
W is the net work done
We are given;
Q = 74.6 kJ
But Q will be negative since heat is released
Thus;
ΔU = -74.6 kJ + W
We are given;
Constant pressure; P = 35 atm = 35 × 101325 = 3546375 N/m²
Volume before reaction; Vi = 8.2 L = 0.0082 m³
Volume after reaction; V_f = 2.8 L = 0.0028 m³
Now,
W = -P(V_f - V_i)
W = - 3546375(0.0028 - 0.0082)
W = 19.15 KJ
Thus;
ΔU = Q + W
ΔU = -74.6 kJ + 19.15 KJ =
ΔU = −55.45 kJ
Answer:
It makes the pasta to get hot faster and boil quicker.
Explanation:
Adding salt to water actually raises the boiling point of the water, due to a phenomenon called boiling point elevation. Essentially, adding any non-volatile solute such as salt to a liquid causes a decrease in the liquid’s vapour pressure. A liquid boils when the vapour pressure above it equals atmospheric pressure, so a lower vapour pressure means you need a higher temperature to boil the water. The reason salt makes water boil faster has to do with specific heat capacities, or the energy it takes to raise the temperature of a substance. Salt ions dissolved in water bind to water molecules, holding them stable and making it harder for them to move around. As a result, the non-salt bound water molecules receive more of the energy provided by the stove, and therefore they get hot faster and boil quicker.
To estimate the molar mass of the gas, we use Graham's law of effusion. This relates the rates of effusion of gases with their molar mass. We calculate as follows:
r1/r2 = √(m2/m1)
where r1 would be the effusion rate of the gas and r2 is for CO2, M1 is the molar mass of the gas and M2 would be the molar mass of CO2 (44.01 g/mol)
r1 = 1.6r2
1.6 = √(44.01 / m1)
m1 = 17.19 g/mol
Answer:
None of these cause the correct answer is 9/-5
