Answer:
it talks about reality ..how animals and human came to existence and how they disappear ..this is evolution
the environment chooses those who best fit in it and others are selected ..as in die ..this is referred to as natural selection
and further in this theory .animals produce off springs who survive in the environment
Answer:
C. Fe will stay positive and increase in magnitude.
Explanation:
Coulomb's law states that the force of attraction of repulsion between two charged particles is directly proportional to the magnitude of their charges and inversely proportional to the square of the distance of separation between them.
This means that if the size of the charges are large, the force acting on them will be large as well. Also if the distance between the two charges increases the force decreases. However, the force increases when the distance of separation decreases.
Like charges repel, therefore, two negative charges brought together will repel each other, and the distance between the two charges decreases, the force will increase in magnitude. Forces of repulsion are considered positive, therefore, the force, Fe, will stay positive and increase in magnitude.
Answer: The moles of gas present in the cylinder is 0.34 moles.
Explanation:
Given:
= 2.7 atm,
= 3.1 L,
= 300 K
= ?,
= 9.4 L,
= 610 K
Formula used to calculate the final temperature is as follows.

Substitute the values into above formula as follows.

Now, moles present upon heating the cylinder are as follows.

Thus, we can conclude that moles of gas present in the cylinder is 0.34 moles.
An electrolyte is a substance that produces an electrically conducting solution when dissolved in a polar solvent, such as water. The dissolved electrolyte separates into cations and anions, which disperse uniformly through the solvent. Electrically, such a solution is neutral.
Hope this helps!!
:)
Answer:
Explanation:
Given parameters;
pH = 8.74
pH = 11.38
pH = 2.81
Unknown:
concentration of hydrogen ion and hydroxyl ion for each solution = ?
Solution
The pH of any solution is a convenient scale for measuring the hydrogen ion concentration of any solution.
It is graduated from 1 to 14
pH = -log[H₃O⁺]
pOH = -log[OH⁻]
pH + pOH = 14
Now let us solve;
pH = 8.74
since pH = -log[H₃O⁺]
8.74 = -log[H₃O⁺]
[H₃O⁺] = 10⁻
[H₃O⁺] = 1.82 x 10⁻⁹mol dm³
pH + pOH = 14
pOH = 14 - 8.74
pOH = 5.26
pOH = -log[OH⁻]
5.26 = -log[OH⁻]
[OH⁻] = 10
[OH⁻] = 5.5 x 10⁻⁶mol dm³
2. pH = 11.38
since pH = -log[H₃O⁺]
11.38 = -log[H₃O⁺]
[H₃O⁺] = 10⁻
[H₃O⁺] = 4.17 x 10⁻¹² mol dm³
pH + pOH = 14
pOH = 14 - 11.38
pOH = 2.62
pOH = -log[OH⁻]
2.62 = -log[OH⁻]
[OH⁻] = 10
[OH⁻] =2.4 x 10⁻³mol dm³
3. pH = 2.81
since pH = -log[H₃O⁺]
2.81 = -log[H₃O⁺]
[H₃O⁺] = 10⁻
[H₃O⁺] = 1.55 x 10⁻³ mol dm³
pH + pOH = 14
pOH = 14 - 2.81
pOH = 11.19
pOH = -log[OH⁻]
11.19 = -log[OH⁻]
[OH⁻] = 10
[OH⁻] =6.46 x 10⁻¹²mol dm³