Answer: True
Explanation: They are formed by the cooling and hardening of molten magma
Answer:
During ice ages, the most characteristic change to the planet has been the formation and spread large ice sheets and glaciers across much the Northern Hemisphere.
Answer:
10
Explanation:
pH is defined as the negative logarithm of the concentration of hydrogen ions.
Thus,
pH = - log [H⁺]
Thus, from the formula, more the concentration of the hydrogen ions or more the acidic the solution is, the less is the pH value of the solution.
Thus, solution with pH = 3 will be more acidic than solution with pH =4
Thus, concentration of the [H⁺] when pH =3
3 = - log [H⁺]
[H⁺] = 10⁻³ M
For pH = 4, [H⁺] = 10⁻⁴ M
<u>hence, pH = 3 is 10 times more acidic than pH = 4</u>
Se2- has 34 protons and 36 electrons so it gets a 2- charge.
Answer:
Explanation: A yellow precipitate o lead iodide is formed. see equation of reaction below: 
→ 
Th PbI2 is the insoluble yellow precipitate
