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3 years ago

What metal will have properties most similar to those of chromium (Cr)? Why?

1 answer:

5 0

That element is manganese. As they are in same horizontal row (period) and are next to each other. That is why they show same properties.

Hope this helps xox :)

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83ef0c8

kumpel [21]

Answer:

0.17325 moles per liter per second

Explanation:

For a first order reaction;

in[A] = in[A]o - kt

Where;

[A]= concentration at time t

[A]o = initial concentration

k= rate constant

t= time taken

ln0.5 =ln1 - 2k

2k = ln1 - ln0.5

k= ln1 - ln0.5/2

k= 0 -(0.693)/2

k= 0.693/2

k= 0.3465 s-1

Rate of reaction = k[A]

Rate = 0.3465 s-1 × 0.50 mol/L

Rate = 0.17325 moles per liter per second

5 0

2 years ago

You want to know how many moles of gas your lungs can hold. You start off with a balloon that has 1.4 moles of gas and occupies

Mrrafil [7]

Number of moles : n₂ = 1.775 moles

<h3>Further explanation</h3>

Given

Moles = n₁ = 1.4

Volume = V₁=22.4 L

V₂=28.4 L

Required

Moles-n₂

Solution

Avogadro's hypothesis, at the same temperature and pressure, the ratio of gas volume will be equal to the ratio of gas moles

The ratio of gas volume will be equal to the ratio of gas moles

$\tt \dfrac{V_1}{V_2}=\dfrac{n_1}{n_2}$

Input the values :

n₂ = (V₂ x n₁)/V₁

n₂ = (28.4 x 1.4)/22.4

n₂ = 1.775 moles

4 0

3 years ago

Our day is 24 hours long because that is the time it takes the earth to

Marianna [84]

Complete one rotation.

Hope this helps.

3 0

2 years ago

Read 2 more answers

A solution is prepared by mixing 2.17 g of an unknown non-electrolyte with 225.0 g of chloroform. The freezing point of the resu

Deffense [45]

Answer:

The molar mass of the unknown non-electrolyte is 64.3 g/mol

Explanation:

Step 1: Data given

Mass of an unknown non-electrolyte = 2.17 grams

Mass of chloroform = 225.0 grams

The freezing point of the resulting solution is –64.2 °C

The freezing point of pure chloroform is – 63.5°C

kf = 4.68°C/m

Step 2: Calculate molality

ΔT = i*kf*m

⇒ ΔT = The freezing point depression = T (pure solvent) − T(solution) = -63.5°C + 64.2 °C = 0.7 °C

⇒i = the van't Hoff factor = non-electrolyte = 1

⇒ kf = the freezing point depression constant = 4.68 °C/m

⇒ m = molality = moles unknown non-electrolyte / mass chloroform

0.7 °C = 1 * 4.68 °C/m * m

m = 0.150 molal

Step 3: Calculate moles unknown non-electrolyte

molality = moles unknown non-electrolyte / mass chloroform

Moles unknown non-electrolyte = 0.150 molal * 0.225 kg

Moles unknown non-electrolyte = 0.03375 moles

Step 4: Calculate molecular mass unknown non-electrolyte

Molar mass = mass / moles

Molar mass = 2.17 grams / 0.03375 moles

Molar mass = 64.3 g/mol

The molar mass of the unknown non-electrolyte is 64.3 g/mol

6 0

3 years ago

The rate constant for the reaction 3A equals 4b is 6.00×10 how long will it take the concentration of a to drop from 0.75 to 0.2

Lelu [443]

This question is incomplete, the complete question is;

The rate constant for the reaction 3A equals 4B is 6.00 × 10⁻³ L.mol⁻¹min⁻¹.

how long will it take the concentration of A to drop from 0.75 to 0.25M ?

from the unit of the rate constant we know it is a second reaction order

OPTIONS

a) 2.2×10^−3 min

b) 5.5×10^−3 min

c) 180 min

d) 440 min

e) 5.0×10^2 min

Answer:

it will take 440 min for the concentration of A to drop from 0.75 to 0.25M

Option d) 440 min is the correct answer

Explanation:

Given that;

Rate constant K = 6.00 × 10⁻³ L.mol⁻¹min⁻¹

3A → 4B

given that it is a second reaction order;

k = 1/t [ 1/A - 1/A₀]

kt = [ 1/A - 1/A₀]

t = [ 1/A - 1/A₀] / k

K is the rate constant(6.00 × 10⁻³)

A₀ is initial concentration( 0.75 )

A is final concentration(0.25)

t is time required = ?

so we substitute our values into the equation

t = [ (1/0.25) - (1/0.75)] / (6.00 × 10⁻³)

t = 2.6666 / (6.00 × 10⁻³)

t = 444.34 ≈ 440 min {significant figures}

Therefore it will take 440 min for the concentration of A to drop from 0.75 to 0.25M

Option d) 440 min is the correct answer

6 0

3 years ago