Answer:
768g
Explanation:
We can use to formula 
. Here, N(A) is the final amount. N0 is the initial amount. t is the time elapsed, and 
is the half life. Plugging in, we get the answer above.
Answer:
C) ball rollinflown a hill
Explanation:
The question asks to identify the endothermic process in the list of options. By way of elimination, we have;
A) condensation of water on a wind shield of a car
Condensation is an exothermic process. That is, heat is given out as the gases change into the liquid state of matter.
B) formation of copper
This is an exothermic process. Capture of electrons by a cation is always exothermic.
C) ball rollinflown a hill
This is the correct option. Energy is absorbed by the ball as it moves on the hill
D) formation of ice from liquid water
Freezing is an example of exothermic reaction. Heat is given off to the surroundings.
E) oxide from copper and oxygen
Formation of metal oxides and most reactions involving oxygen are exothermic reactions,
Answer:
Buffer 1.
Explanation:
Ammonia is a weak base. It acts like a Bronsted-Lowry Base when it reacts with hydrogen ions.
.
gains one hydrogen ion to produce the ammonium ion 
. In other words, is the conjugate acid of the weak base .
Both buffer 1 and 2 include
- the weak base ammonia , and
- the conjugate acid of the weak base .
The ammonia in the solution will react with hydrogen ions as they are added to the solution:
.
There are more in the buffer 1 than in buffer 2. It will take more strong acid to react with the majority of in the solution. Conversely, the pH of buffer 1 will be more steady than that in buffer 2 when the same amount of acid has been added.
They are in order according to their atomic number, so the position should tell you the atomic number.
Neon I think. Go to the periodic table and see which one is the 11th
