What does below science rebus mean?

Ag Ag Ag
Ag SPOON Ag
Ag Ag Ag

John was working on a Chemical Mixture whose weight comprise 90% liquid and 10% solid. The total weight of the mixture is 20 pounds. After a while, John noticed that some of the liquid evaporated and now the liquid comprises just 50% of the weight.

What is the weight of the chemical mixture now?

A patient was diagnosed with some ailment. He was given five different tablets to take at night at an interval of 15 minutes.

How long will it take the patient to consume all the five tablets?

Arrange the numbers 1, 2, 3, 4, 5, 6, 7, 8 and 9 above and below the division line in a manner that the thus formed fractions equal to 1/3.

(You can use one number only once)

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

What is the Surname of Barbie Doll?

Without looking at a calendar, within a minute name, a boy's name using 5 consecutive 1st letters of 5 consecutive months

Can you identify the Oscar-winning movie from the rebus below?

Two in a corner, one in a room, zero in a house, but one in a shelter. What am I?

What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day