<u>Answer:</u> The density of NaCl solution is 3.930 g/mL
<u>Explanation:</u>
We are given:
Mass of cylinder,
= 21.577 g
Mass of NaCl and cylinder combined, M = 39.664 g
Mass of NaCl,
= 
To calculate density of a substance, we use the equation:

We are given:
Mass of NaCl = 18.087 g
Volume of NaCl solution = 4.602 mL
Putting values in above equation, we get:

Hence, the density of NaCl solution is 3.930 g/mL
<u>Answer:</u> The value of <em>i</em> is 1.4 and 40% dissociation of 100 particles of zinc sulfate will yield 60 undissociated particles.
<u>Explanation:</u>
The equation used to calculate the Vant' Hoff factor in dissociation follows:

where,
= degree of dissociation = 40% = 0.40
i = Vant' Hoff factor
n = number of ions dissociated = 2
Putting values in above equation, we get:

The equation used to calculate the degee of dissociation follows:

Total number of particles taken = 100
Degree of dissociation = 40% = 0.40
Putting values in above equation, we get:

This means that 40 particles are dissociated and 60 particles remain undissociated in the solution.
Hence, 40% dissociation of 100 particles of zinc sulfate will yield 60 undissociated particles.
21.69mL - 20.70mL = .99mL Fe
7.8 g / .99 mL = 7.9g/mL
A computer screen is energy transfer
Explanation:
when water is boiling and when u cover it and increase the pressure it causes the increase in rate of condensation.