Atomic mass Boron ( B ) = 10.811 u.m.a
10.811 g -------------- 6.02x10²³ atoms
5.40 g ----------------- ?? atoms
5.40 x ( 6.02x10²³) / 10.811 =
3.0069x10²³ atoms
Could you post another question with a photo? I am sorry...
In rubidium oxide - Rb₂O , the ions are Rb⁺ and O²⁻
Rb is a group one element with one valence electron. To become stable it loses its outer electron to gain a complete outer shell.
Electronic configuration of Rb is - 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 5s¹
Once it loses its valence electron the configuration is;
- 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶
The noble gas with this configuration is Krypton - Kr
Oxygen electron configuration is 1s² 2s² 2p⁴
Once it gains 2 electrons the configuration is - 1s² 2s² 3p⁶
The noble gas with this configuration is Neon - Ne
The wheels will be completely used up and it is the limiting reactant in this case.
<h3>What is a limiting reactant?</h3>
The limiting reactant is the reactant that is completely used up in a reaction, and thus determines when the reaction stops.
- 60 breaks will be used for 30 engines and 30 body frame
- 80 wheels will be used for 20 engines and 20 body frame
- 64 headlights will be used for 32 engines and 32 body frame
The wheels will be completely used up and it is the limiting reactant in this case.
Learn more about limiting reactants here: brainly.com/question/14222359
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