1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
maw [93]
3 years ago
9

A quantity of 1.922 g of methanol (CH3OH) was burned in a constant-volume bomb calorimeter. Consequently, the temperature rose b

y 5.72°C. If the heat capacity of the bomb plus water was 9.47 kJ / °C, calculate the molar heat of combustion of methanol.
Chemistry
1 answer:
dezoksy [38]3 years ago
5 0

Answer:

872.28 kJ/mol

Explanation:

The heat released is:

ΔH = C*ΔT

where ΔH is the heat of combustion, C is the heat capacity of the bomb plus water, and ΔT is the rise of temperature. Replacing with data:

ΔH =  9.47*5.72 = 54.1684kJ

A quantity of 1.922 g of methanol in moles are:

moles = mass / molar mass

moles = 1.992/32.04 = 0.0621 mol

Then the molar heat of combustion of methanol is:

ΔH/moles = 54.1684/0.0621 = 872.28 kJ/mol

You might be interested in
Please please please please help
deff fn [24]
I’ll give u my number and I’ll send u a pic of the answers
8 0
2 years ago
What is the molarity of a sodium hydroxide solution containing 2 moles of NaOH with a volume of .5L?
Maksim231197 [3]

Answer:

0.4M NaOH

Explanation:

Molarity, M, is an unit of concentration widely used defined as the ratio between moles of solute (In this case, NaOH) and volume of solution in liters.

As the solution contains 2 moles of NaOH-Moles of solute- in 5L of solution, the molarity is:

2 moles NaOH /  5L =

<h3>0.4M NaOH</h3>
5 0
2 years ago
It would be nice if someone HELPED. During an experiment, you observe that two charged balloons repel each other. When you bring
jeka57 [31]

Answer:

They are similarly charged, which is why they repel each other.

8 0
2 years ago
Read 2 more answers
2+2=? -1 3 quick math
tino4ka555 [31]
EVERYDAY MANS ON THE BLOCK. Lol its 4. You got this from Mans Not Hot, didn't you? xD
4 0
3 years ago
Read 2 more answers
Five kilograms of liquid carbon tetrachloride undergo a mechanically reversible, isobaric change of state at 1 bar during which
Drupady [299]

Answer:

Explanation:

From the information given:

Mass of carbon tetrachloride = 5 kg

Pressure = 1 bar

The given density for carbon tetrachloride = 1590 kg/m³

The specific heat of carbon tetrachloride =  0.84 kJ/kg K

From the composition, the initial volume of carbon tetrachloride will be:= \dfrac{5 \ kg }{1590 \ kg/m^3}

= 0.0031 m³

Suppose \beta is independent of temperature while pressure is constant;

Then:

The change in volume can be expressed as:

\int ^{V_2}_{V_1} \dfrac{dV}{V} =\int ^{T_2}_{T_1} \beta dT

In ( \dfrac{V_2}{V_1})  = \beta (T_2-T_1)

V_2 = V_1 \times exp (\beta (T_2-T_1))

V_2 = 0.0031 \ m^3  \times exp  (1.2 \times 10^{-3} \times 20)

V_2 = 0.003175 \ m^3

However; the workdone = -PdV

W = -1.01 \times 10^5 \ Pa \times ( 0.003175 m^3 - 0.0031 \ m^3)

W = - 7.6 J

The heat energy Q = Δ h

Q = mC_p(T_2-T_1)

Q = 5 kg \times 0.84 \ kJ/kg^0 C \times 20

Q = 84 kJ

The internal energy is calculated by using the 1st law of thermodynamics; which can be expressed as;

ΔU = ΔQ + W

ΔU = 84 kJ + ( -7.6 × 10⁻³ kJ)

ΔU = 83.992 kJ

3 0
3 years ago
Other questions:
  • The key on a pie chart represents...
    10·2 answers
  • The reported molar mass for the copper oxide formed in experiment 1 is 79.55 g/mol. what is the molecular formula of the oxide f
    9·1 answer
  • Molecules can be constructed by combining atoms of the same element. True or false?
    11·2 answers
  • Gallium oxide, Ga.Oy, forms when gallium is combined with oxygen. A 1.25 g of Ga is allowed to react with excess oxygen and 1.68
    13·1 answer
  • A beaker contains 450 g of water (H2O). If 9.2 g of calcium fluoride (CaF2) is added, what is the molality concentration of the
    8·1 answer
  • Based on the kinetic theory, which statement is true?
    5·1 answer
  • Suppose of iron(II) bromide is dissolved in of a aqueous solution of silver nitrate. Calculate the final molarity of bromide ani
    10·1 answer
  • Is it possible for a child to have a dna band that is not found in the mother's dna? Explain
    15·2 answers
  • How is hydrogen in heavy water different from hydrogen in normal water?
    5·2 answers
  • Which has the larger change hydration in each pair of a)Na+ Or cs+ b)Sr+2 or Rb+ c)Na+ or Cl- d) O-2 or F- e)OH- or SH-
    13·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!