Question

A student measures the pH of a solution to be 6.8. Which should the student add if she wants to decrease the pH of the solution?

NaCl
H2O
HF
KOH

Answer 1

c or d

Answer 2

hint:
we have to get the partial neutralization of the acid, and it is possible only if we add an hydroxide

Answer 3

so c

Answer 4

option C is an acid

Answer 5

oh ok then D KOH

Answer 6

that's right!

Answer 7

Thank You!

Answer 8

:)

Answer 9

one more

Answer 10

As heat is added to a tube of gas, which is the most likely phase transition to occur in the tube?

gas to plasma
gas to liquid
gas to solid
gas to element

Answer 11

I think that if we add heat, then options B and C can not be possible

Answer 12

It should be turned to plasma.

Answer 13

I think so! Since an ionization of the molecules of the gas it is possible

Answer 14

depending on the quantity of heat I am adding to the gas

Answer 15

generally the ionization of a gas is obtained by means of the collisions among the molecules of that gas with a beam of accelerated electrons

Answer 16

I think it is option A, nevertheless I'm not sure

Answer 17

Agree. Giving enough heat will turn the gas to plasma by increasing collisions.