Answer:
option b. B3+
Explanation:
Boron takes the 5th position on the periodic table, therefore it has 5 electrons....2 on the inside and 3 on the outside. when it lost it 3 external electrons, it become positively charged with the amount of electron it loses.
The answer I would choose is the third one
please have look at Periodic table , you will solve it yourself !
Molar mass Na = 23.0 g/mol
1 mol ---- 23.0 g
n mol ---- 69 g
n = 69 / 23.0
n = 3.0 moles
1 mole -------- 6.02x10²³ molecules
3.0 moles ---- ?
3.0 * 6.02x10²³ / 1
= 1.806x10²⁴ molecules
hope this helps!
Answer:
The answer to your question is the letter A. 1
Explanation:
Unbalanced chemical reaction
Mg + O₂ ⇒ MgO
Reactants Elements Products
1 Magnesium 1
2 Oxygen 1
Balanced chemical reaction
2Mg + O₂ ⇒ 2MgO
Reactants Elements Products
2 Magnesium 2
2 Oxygen 2
Conclusion
The coefficients of the balanced equation are 2, 1, 2
