Explanation:
It is more difficult to remove electrons from the second shell or energy level because of the imbalance between the positive nuclear charge and the remaining electrons.
- The amount of energy required to remove electrons in ground state of an atom is the ionization energy.
- The first ionization energy is the energy needed to remove the most loosely bound electron of an atom in the gas phase in ground state.
- The second energy has a greater nuclear pull as it is closer to the nucleus.
- Both potassium and silicon have the same number of energy levels.
Answer:

Explanation:
Given that,
The specific heat of water is 4.184Jg°C
Mass, m = 600 g
Initial temperature, T₁ = 75.5°C
We need to find the final temperature. We know that heat absorbed is given by :

So, the final temperature is equal to
.
Answer:
50 g
Explanation:
d= m/v
rearranging the above equation
m = d x v
m = 2.5 g x 20 g/cm3
m = 50 g
The negative ion in aqueous sodium hydroxide, NaOH(aq) is hydroxide ion, OH-.
<h3>What is a neutralization reaction?</h3>
A neutralization reaction is a reaction between an acid and a base to form salt and water only.
The reaction between vinegar and NaOH is a neutralization reaction which produces a salt and water only.
NaOH is composed of a positive sodium ion, Na+ and a negative hydroxide ion, OH-
Therefore, the negative ion in the NaOH(aq) used in this titration is hydroxide ion, OH-.
Learn more about hydroxide ion at: brainly.com/question/3078877