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
Answer:
Ksp = 2.74 x 10⁻⁵
Explanation:
The solubility equilibrium for Ca(OH)₂ is the following:
Ca(OH)₂(s) ⇄ Ca²⁺(aq) + 2 OH⁻(aq)
I 0 0
C + s + 2s
E s 2s
According to the ICE table, the expression for the solubility product constant (Kps) is:
Ksp = [Ca²⁺] x ([OH⁻])² = s x (2s)² = 4s³
Then, we calculate Ksp from the solubility value (s):
s = 0.019 M
⇒ Ksp = 4s³ = 4 x (0.019)³ = 2.74 x 10⁻⁵
Answer:
The particles move faster and are far apart
Explanation:
A substance may exist in three states of matter; solid, liquid and gas.
In the solid state, there is very strong intermolecular forces between the particles of the substance. They can only vibrate or rotate about their mean positions but can not translate.
In the liquid state, the particles of the substance have a greater degree of freedom than in the solid. The magnitude of intermolecular forces is lower than in solids, the molecules can move at low speeds.
In a gas, the molecules are separated from each other with negligible intermolecular interaction hence they move at very high speed.
Therefore, for the water gas particles in the air above the cup; the particles move faster and are far apart.
Hello!
In an endothermic reaction, The potential energy of the products is greater than the potential energy of the reactants.
Any chemical reaction that absorbs energy is called an Endothermic Reaction. In this reactions, the reactants absorb energy from the surroundings to carry out the reaction. As a result, the products have a higher potential energy than the reactants. Photosynthesis is an example of an Endothermic Reaction, as the plant uses energy from the sun to generate the products.
Have a nice day!