All categories

3 years ago

What is the mass of phosphorus that contains twice the number of atoms found in 14

Chemistry

1 answer:

yulyashka [42]3 years ago

3 0

Answer:

15.5 gm

Explanation:

What is the mass of phosphorus that contains twice the number of atoms found in 14 g of iron?

[Relative atomic mass : P = 31; Fe = 56]

14 gm Fe = 14gm/ 56 gm/mole = 14 mole gm/56gm = 14/56 mole

0.25 moles

2 X 0.25 = 0.5 moles

1 mole P = 31 gm

0.5 moles P =31/2 =15.5 gm

You might be interested in

General Chemistry fourth edition by McQuarrie, Rock, and Gallogly. University Science Books presented by Macmillan Learning.

Helen [10]

Answer:

3.07 Cal/g

Explanation:

Step 1: Calculate the heat absorbed by the calorimeter

We will use the following expression.

Q = C × ΔT

where,

Q: heat absorbed

C: heat capacity of the calorimeter (37.60 kJ/K = 37.60 kJ/°C)

ΔT: temperature change (2.29 °C)

Q = 37.60 kJ/°C × 2.29 °C = 86.1 kJ

According to the law of conservation of energy, the heat released by the candy has the same magnitude as the heat absorbed by the calorimeter.

Step 2: Convert 86.1 kJ to Cal

We will use the conversion factor 1 Cal = 4.186 kJ.

86.1 kJ × 1 Cal/4.186 kJ = 20.6 Cal

Step 3: Calculate the number of Cal per gram of candy

20.6 Cal/6.70 g = 3.07 Cal/g

3 0

3 years ago

How many half-lives are required for the concentration of reactant to decrease to 1.56% of its original value?4247.56.56

neonofarm [45]

Answer:

6 half-lives are required for the concentration of reactant to decrease to 1.56% of its original value.

Explanation:

Using integrated rate law for first order kinetics as:

$[A_t]=[A_0]e^{-kt}$

Where,

$[A_t]$ is the concentration at time t

$[A_0]$ is the initial concentration

Given:

Concentration is decreased to 1.56 % which means that 0.0156 of $[A_0]$ is decomposed. So,

$\frac {[A_t]}{[A_0]}$ = 0.0156

Thus,

$\frac {[A_t]}{[A_0]}=e^{-k\times t}$

$0.0156=e^{-k\times t}$

kt = 4.1604

The expression for the half life is:-

Half life = 15.0 hours

$t_{1/2}=\frac {ln\ 2}{k}$

Where, k is rate constant

So,

$k=\frac {ln\ 2}{t_{1/2}}$

$\frac{4.1604}{t}=\frac {ln\ 2}{t_{1/2}}$

$t = 6\times t_{1/2}$

<u>6 half-lives are required for the concentration of reactant to decrease to 1.56% of its original value.</u>

6 0

3 years ago

What is Delta.Gsystem for the system that is described by the following data? Delta.Hsystem = –345 kJ, T = 293 K, Delta.Ssystem

ryzh [129]

Answer:

-209 kJ

Explanation:

I did the math. You're welcome ;)

6 0

3 years ago

What is the ph value of the produced solution when hcl reacts with naoh ?

algol13

Answer:

The answer to your question is: 7

Explanation:

The reaction between HCl and NaOH is a neutralization reaction, that means that the products will be water and a salt and the pH will be 7.

HCl + NaOH ⇒ NaCl + H₂O

4 0

3 years ago

How can a person reduce consumption of natural resources when drinking water? Assume that you are not going to change the amount

miss Akunina [59]

Answer:

It will reduce the natural resources by not littering, putting trash in the recycle bin or trash bin. I will also keep drinking the normal amount a day which would be 3-4 bottles of water. I will also not throw my trash on the ground or any thing like that it will stay with me until i'm near a trash can. If you litter than you are ki**ing a poor innocent animal or mammal so please don't litter.

Explanation:

l'm sorry if its wrong but hope it helps you

4 0

2 years ago