Question

Three questions:

1) The electronic configuration of an element is 1s²2s²2p⁶. How many valence electrons does it have?

2
4
6
8

2) In an experiment, 132 g of potassium bromide (KNO3) was dissolved in 100 grams of water at 70 °C in 1 minute.

Which of the following will most likely happen if the sample of potassium phosphate is dissolved in 100 grams of water at 20 °C?

The number of collisions between particles will increase.
The number of collisions between particles will remain constant.
A greater number of particles of the sample will dissolve in 1 minute.
A fewer number of particles of the sample will dissolve in 1 minute.

3) Which statement is true about HCl?

It is a salt because it increases the concentration of metallic ions.
It is a salt because it is formed by the reaction of an acid and a base.
It is an acid because it increases the concentration of hydroxide ions.
It is an acid because it increases the concentration of hydrogen ions.

Answer 1

There is 3 separate questions :)

Answer 2

For the first one: it only wants valence electrons, so only add the electrons in the outermost level (in this case, only the 2s and 2p sub shells)

Answer 3

For the second one: solubility decreases as temperature decreases - so if we drop the temperature from 70 to 20 C, do you think more or less will dissolve?

Answer 4

For the third one: HCl dissociates into H+ and Cl-. What does this mean in terms of acid/base properties?

Answer 5

hold on I think I have the answers

Answer 6

I think the answers are
1) D
2) D
3) D

Answer 7

tell me if I'm wrong

Answer 8

Good