Answer:
B) Add appropriate quantities of weak acid and its conjugate base to water.
C) Partially neutralize a weak acid solution by addition of a strong base.
(D) Partially neutralize a weak base solution by addition of a strong acid.
Explanation:
A buffer solution is made by a weak acid and its conjugated base or a weak base and its conjugated acid.
If you add a weak acid to water, you can adjust the pH of the buffer solution by adding a strong base.
If ypu add a weak base to water, you can adjust the pH of the buffer solution by adding a strong acid.
Answer:
So, you're dealing with a sample of cobalt-60. You know that cobalt-60 has a nuclear half-life of
5.30
years, and are interested in finding how many grams of the sample would remain after
1.00
year and
10.0
years, respectively.
A radioactive isotope's half-life tells you how much time is needed for an initial sample to be halved.
If you start with an initial sample
A
0
, then you can say that you will be left with
A
0
2
→
after one half-life passes;
A
0
2
⋅
1
2
=
A
0
4
→
after two half-lives pass;
A
0
4
⋅
1
2
=
A
0
8
→
after three half-lives pass;
A
0
8
⋅
1
2
=
A
0
16
→
after four half-lives pass;
⋮
Explanation:
now i know the answer
<h2>Answer:</h2>
B) endothermic reaction.
<h2>Explanation:</h2>
Melting of ice is endothermic because it is taking heat from the environment, feeling cold, because it requires energy to break the ice bonds. It's also why you feel cold when wet it takes energy to evaporate water. The ice absorbs the energy from the environment. Its internal potential energy increases, therefore, it's endothermic. It also increases the entropy of reaction.
Sublimation occurs more readily when definite weather circumstances are present such as low relative humidity and dry winds. Sublimation also occurs more at higher altitudes where the air pressure is less than at lower altitudes and energy such as strong sunlight is also needed. Sublimation happens a lot in the south face of Mt. Everest which have low temperatures, strong winds, intense sunlight, very low air pressure and the recipe for sublimation to occur.
