Anything with a pH level of 3, 2, or 1.
Answer:

Explanation:
Group 4A contains a total of 4 electrons for each atom in their valence shell. Filling the orbital diagram, let's say, for carbon, notice that when we start with period 2, we have two elements in the s-block, that is, lithium and beryllium. They correspond to the two s electrons that belong to the valence shell of carbon.
Moving on, we have boron and carbon, the remaining 2 electrons. Now, starting with boron, we're in the p-block.
That said, looking at the second period, the electron configuration for the valence shell of a group 4A element would be:

The mass stays the same because if you have the same amount of steam then it can't change. The volume will get slightly smaller because the average kinetic energy of the molecules is less, so they move around less, so they take up less space. The particles are moving less fast.
Answer:
They are all the same = 8
Explanation:
Since the symbol of that atom is not give, we can infer from the given number the nature and kind of element we are dealing with.
The number 15.999 rounded up to 16 is the atomic weight of the atom also called the mass number.
Although not peculiar enough, we are certain that this atom is Oxygen.
On the periodic table, elements are arranged based on their atomic numbers.
Atomic number of oxygen = 8 = number of protons
For every neutral atom on the periodic table, the number of protons and electrons are the same
Atomic number of oxygen = number of protons = number of electrons = 8
Number of neutrons = Mass number - atomic number = 16 - 8 = 8