The answers are :
1 - F
2- T
Answer:

Explanation:
This reaction type is a single replacement. The format of a single replacement is:

A= Al
B= Ni
C= SO
The coefficient 3 for Ni would become a subscript for AC. After you plug those into the reaction you need to count how many of each are on the left side and try to get the same number on the right side. Both sides must be equal to have a balanced equation.
Answer:
The total energy, i.e. sum of kinetic and potential energy, is constant.
i.e. E = KE + PE
Initially, PE = 0 and KE = 1/2 mv^2
At maximum height, velocity=0, thus, KE = 0 and PE = mgh
Since, total energy is constant (KE converts to PE when the ball is rising),
therefore, KE = PE
or, 1/2 mv^2 = mgh
or, h = v^2 /2g = 13^2 / (2x9.8) = 8.622 m
Hope this helps.
Answer: Option (D) is the correct answer.
Explanation:
Atomic number of chlorine is 17 and its electronic distribution is 2, 8, 7.
So, in order to attain stability it tends to gain one electron from a donor atom. Therefore, a chlorine ion is formed as
.
As it gains only one electron that is why, -1 charge occurs.
Whereas Ar is a noble gas with atomic number 18. As it has completely filled octet so it will be unreactive in nature as it is already stable.
Similarly, He is also a noble gas so it is unreactive in nature.
Atomic number of boron (B) is 5 with electronic distribution 2, 3. So, in order to attain stability it needs to lose 3 electrons.
Thus, we can conclude that Cl is the atom which tends to gain 1 valence electron from another atom in order to become stable.