I am sure it is a.12150sn and 11950sn because isotopes are the same atoms but different number of protons
Answer:
1.204 × 10²³
Explanation:
The number of atoms in a mole is always 6.022 × 10²³, known as Avogadro's number or Avogadro's constant.
To convert moles to atoms, multiply the molar amount by Avogadro's number.
(6.022 × 10²³) × 0.2
= 1.204 × 10²³
Answer:
K
Explanation:
Since the blood moves from the body to the right atrium to the right ventricle
Oxygen (O), Sulphur (S) and Selenium (Se) have similar chemical properties because they all have the same number of electrons in their outermost shells.
Atoms with the same number of electrons in their outermost shells can be found in the same group.
A group consists of elements arranged in the same column (from top to bottom) on the periodic table. Elements on the same group have similar chemical properties.
Oxygen (O), Sulphur (S) and Selenium (Se) are in group eight. All three elements are highly electronegative and have 6 electrons in their outermost shell. They also carry ab charge of -2.
To learn more about the periodic table, visit:
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They are important because they are the electrons that help the atom to bond with another atom. They are in the outer most shell. ☺️