All categories

2 years ago

PLEASE HELP!!!

Chemistry

1 answer:

trasher [3.6K]2 years ago

4 0

Answer:

(a) oxygen

(b) 154g (to 3sf)

Explanation:

mass (g) = moles × Mr/Ar

note: eqn means chemical equation

(a)

moles of P = 84.1 ÷ 30.973 = 2.7152 moles

moles of O2 = 85÷2(16) = 2.65625 moles

Assuming all the moles of P is used up,

moles of O2 / moles of phosphorus = 5/4 (according to balanced chemical eqn)

moles of O2 required = 5/4 × 2.7152moles = 3.394 moles (more than supplied which is 2.65625moles)

therefore there is insufficient moles of O2 and the limiting reactant is oxygen.

(b)

moles of P2O5 produced

= 2/5 (according to eqn) × 2.7152

= 1.08608moles

mass of P2O5 produced

= 1.08608 × [ 2(30.973) + 5(16) ]

= 154.164g

= approx. 154g to 3 sig. fig.

(c)

% yield = actual/theoretical yield × 100%

= 123/154 × 100%

= 79.870%

= approx. 79.9% (to 3sf)

You might be interested in

Consider the following reaction at equilibrium: 2 NH3(g) ⇄ N2(g) + 3 H2(g) What does Le Chatelier's principle predict will happe

BabaBlast [244]

Answer : The equilibrium will shift in the left direction.

Explanation :

Le-Chatelier's principle : This principle states that if any change in the variables of the reaction, the equilibrium will shift in the direction to minimize the effect.

The given reaction is:

$2NH_3(g)\rightleftharpoons N_2(g)+3H_2(g)$

As per question, when we are adding $N_2$ then the concentration of $N_2$ is increased on product side then the equilibrium will shift in the direction where decrease of concentration of $N_2$ takes place. Therefore, the equilibrium will shift in the left direction.

Thus, the equilibrium will shift in the left direction.

7 0

3 years ago

CH4 + O2 → CO2 + H2O

Scilla [17]

Answer:

9.8 × 10²⁴ molecules H₂O

General Formulas and Concepts:

Atomic Structure

Reading a Periodic Table
Moles
Avogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.

Organic

Naming carbons

Stoichiometry

Analyzing reaction rxn
Using Dimensional Analysis

Explanation:

Step 1: Define

[RxN - Unbalanced] CH₄ + O₂ → CO₂ + H₂O

[RxN - Balanced] CH₄ + 2O₂ → CO₂ + 2H₂O

[Given] 130 g CH₄

Step 2: Identify Conversions

Avogadro's Number

[RxN] 1 mol CH₄ → 2 mol H₂O

[PT] Molar Mass of C: 12.01 g/mol

[PT] Molar Mass of H: 1.01 g/mol

Molar Mass of CH₄: 12.01 + 4(1.01) = 16.05 g/mol

Step 3: Stoichiometry

[DA] Set up conversion: $\displaystyle 130 \ g \ CH_4(\frac{1 \ mol \ CH_4}{16.05 \ g \ CH_4})(\frac{2 \ mol \ H_2O}{1 \ mol \ CH_4})(\frac{6.022 \cdot 10^{23} \ molecules \ H_2O}{1 \ mol \ H_2O})$
[DA] Divide/Multiply [Cancel out units]: $\displaystyle 9.75526 \cdot 10^{24} \ molecules \ H_2O$

Step 4: Check

Follow sig fig rules and round. We are given 2 sig figs.

9.75526 × 10²⁴ molecules H₂O ≈ 9.8 × 10²⁴ molecules H₂O

8 0

2 years ago

What is cement and who invented it?

Sonja [21]

Answer:

Cement is a combination of calcium, silicone, aluminum, iron and lots of other ingredients to make side walks, home made crafts, etc. The person who invented concrete is Joseph Aspdin.

Explanation:

5 0

3 years ago

Which physical method can be used for obtaining a sample of salt from a small beaker of salt water? boiling freezing filtration

sergij07 [2.7K]

I think it's boiling :)

3 0

3 years ago

Read 2 more answers

1) How much water must be added to 500.mL of 0.200 M HCI to produce a 0.150M solution?

zloy xaker [14]

Answer:

(500.mL)(.200M)/.150M = 667 mL

667mL - 500mL = 167mL of water is needed

1.0 L = 1000mL

M1 V1 = M2 V2

(1.6 mol/L) (175 mL) = (x)(1000mL)

x = .28M

6 0

3 years ago