Answer:
Here
Explanation:
Chemists need the mole concept to bridge the gap between the microscopic world of atoms to the macroscopic world of humans. As you know, the molecular level consists of particles that are invisible to us.
Answer:
= 1.271 J/g°C
Explanation:
Heat released by the metal sample will be equivalent to the heat absorbed by water.
But heat = mass × specific heat capacity × temperature change
Thus;
Heat released by the solid;
= 225 g × c ×(67 -53) , where c is the specific heat capacity of the metal
= 3150 c joules
Heat absorbed by water;
= 25.6 g × 4.18 J/g°C × (53-15.6)
= 4002.0992 joules
Therefore;
3150 c joules = 4002.0992 joules
c =4002.0992/3150
<u> = 1.271 J/g°C</u>
The answer to this question will be C
Answer:
Explanation:
We need to use the formula for heat of vaporization.
Identify the variables.
- The heat absorbed by the evaporating water is the <u>latent heat of vaporization. </u>For water, that is 2260 Joules per gram.
- Q is the energy, in this problem, 50,000 Joules.
- m is the mass, which is unknown.
Substitute the values into the formula.
We want to find the mass. We must isolate the variable, m.
m is being multiplied by 2260 J/g. The inverse operation of multiplication is division. Divide both sides by 2260 J/g.
Divide. Note that the Joules (J) will cancel each other out.
Round to the nearest whole number. The 1 in the tenth place tells us to leave the number as is.
The mass is about 22 grams, so choice B is correct.
The correct answer is (A) from 2nd to 3rd shell.
The explanation :
when a gain of energy is the shift of the electrons from a shell of low energy to the shell of high energy
and we have here 2nd shell is the shell of low energy, and 3rd shell is the shell of high energy.
∴ (A) from 2nd to 3rd shell is the correct answer.