Protons are positive
Neutrons are neutral
Electrons are negatively charged
Answer:
a) Se²⁻> S²⁻ > O²
b) Te²⁻ > I- >Cs+
c) Cs+ > Ba²⁺ > Sr²⁺
Explanation:
(a) Se²⁻, S²⁻, O²⁻
In general, ionic radius decreases with increasing positive charge.
As the charge on the ion becomes more positive, there are fewer electrons.
The ion has a smaller radius. In general, ionic radius increases with increasing negative charge.
For ions of the same charge (e.g. in the same group) the size increases as we go down a group in the periodic table
Se²⁻> S²⁻ > O²
(b) Te²⁻, Cs⁺, I⁻
Te²⁻ > I- >Cs+
Te2- hast the biggest size, because of the double negative charge.
Cs+ has the smallest size since it has the most positive charge, compared to Te2- and I-.
(c) Sr²⁺, Ba²⁺, Cs⁺
Cs+ > Ba²⁺ > Sr²⁺
Cs+ has the biggest size, because its more downward (compared to Sr2+) and more to the left (compared) ot Ba2+.
Sr2+ has the smallest size because it's more upwords (compared to Cs+ and Ba2+)
The number of atoms present, on average, will be the natural abundance of the isotope times the number of atoms in the sample => number of C-13 atoms = C-13 abundance * number of atoms in the sample = 1.07% * 30,000 = 1.07 * 30,000 / 100 = 321 atoms.<span> Answer: 321 atoms.</span>
Tin-120 because an atom has to have a neutral charge. If an atom has 50 electrons it must have 50 protons unless it's an ion. Add 70 to the atomic mass because it has 70 neutrons on top of 50 protons. That equals to 120. Tin has an atomic number of 50 (meaning it has 50 protons) and it has roughly an atomic mass of about 118. If the given has 70 neutrons then it's a isotope of tin.
The reactants in this reaction are sodium and chlorine. Sodium is a soft, silvery-white metal that is highly reactive. Chlorine is a poisonous greenish-yellow gas that has an odor and combines readily with other elements.
This might be the exact question so you might wanna rephrase it but good luck! :)))