Answer:
317.46 °C
Explanation:
The expression for the calculation of heat is shown below as:-
Where,
is the heat absorbed/released
m is the mass
C is the specific heat capacity
is the temperature change
Thus, given that:-
Mass of lead = 118.5 g
Specific heat = 0.129 J/g°C
Initial temperature = 10 °C
Final temperature = x °C
Q = 4700 J
So,
<u>Thus, the final temperature is:- 317.46 °C</u>
Answer:
1) 5.74 L.
2) 67.158 g/mol.
Explanation:
<u><em>Q1:</em></u>
- We suppose that the two gases CH₄ and O₂ behave ideally.
- We can use the general gas law of ideal gases:
<u><em>PV = nRT</em></u>
P is the pressure of the gases (P = 950 torr / 760 = 1.25 atm).
V is the volume of the gases (V = ??? L).
R is the general gas constant (R = 0.082 L.atm/mol.K).
T is the temperature of the gases (T = 400 K).
n is the no. of moles of the gases.
- <em>n = no. of moles of CH₄ + no. of moles of O₂.</em>
no. of moles of CH₄ = mass / molar mass = (2.0 g) / (16.0 g/mol) = 0.125 mol.
no. of moles of O₂ = mass / molar mass = (3.0 g) / (32.0 g/mol) = 0.09375 mol.
∴ n = no. of moles of CH₄ + no. of moles of O₂ = 0.125 mol + 0.09375 mol = 0.21875 mol.
∴ V = nRT/P = (0.21875 mol)(0.082 L.atm/mol.K)(400 K) / (1.25 atm) = 5.74 L.
<em><u>Q2:</u></em>
- We can also use the general gas law: PV = nRT.
- Each term in the law is defined in the answer of the first question.
- n = mass / molar mass, we substitute by this value in the gas law.
<em>PV = (mass/molar mass)RT.</em>
The molar mass = (mass)RT/PV.
The mass of the gas = 0.90 g.
R = 0.082 L.atm/mol.K.
T = 273 K at STP conditions.
P = 1.0 atm at STP conditions.
V = 300.0 mL = 0.30 L.
- The molar mass = (mass)RT/PV = (0.90 g)(0.082 L.atm/mol.K)(273.0 K) / (1.0 atm)(0.30 L) = 67.158 g/mol.
Answer:
the answer is 3. freezing
Answer:
D) hydrochloric acid.
Explanation:
- The balanced equation for the mentioned reaction is:
<em>Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g),</em>
<em></em>
It is clear that 1.0 moles of Zn react with 2.0 moles of HCl to produce 1.0 moles of ZnCl₂ and 1.0 mole of H₂.
- From stichiometry; Zn reacts with HCl with (1: 2) molar ratio.
<em>∴ 2.0 mol of Zn (the remaining 2.0 mol is in excess) react completely with 4.0 mol of HCl with (1: 2) molar ratio.</em>
<em />
So,
the limiting reactant is HCl and the excess reactant is Zn.
<em>Thus, the right choice is: D) hydrochloric acid.</em>
Answer:
Avogadro's law, a statement that under the same conditions of temperature and pressure, equal volumes of different gases contain an equal number of molecules.
