Answer:
B) 8.0 molecules.
Explanation:
- From the balanced equation: <em>3Cu + 8HNO₃ → 3Cu(NO₃)₂ + 2NO + 4H₂O,</em>
It is clear that 3.0 atoms of Cu react with 8.0 molecules of HNO₃ to produce 3.0 molecules of Cu(NO₃)₂, 2.0 molecules of NO, and 4.0 atoms of H₂O.
<u><em>Note that: </em></u>The no. of atoms and molecules is the same ratio to the no. of moles.
<u><em>Using cross multiplication:</em></u>
3.0 atoms of Cu produce → 2.0 molecules of NO, from the balanced equation.
12.0 atoms of Cu produce → <em>??? molecules of NO.</em>
<em>∴ The no. of molecules of NO produced </em>= (2.0 molecules)(12.0 atoms)/(3.0 atoms) = <em>8.0 molecules.</em>
Answer:
1.
- A) protons and neutrons
- B) electrons
2.
- By changing the number of proton.
Explanation:
Protons and neutrons are located at the center of an atom which is nucleus .
Electrons will orbit around the nucleus .
The enthalpy of formation has a negative sign, which means that the reaction is exothermic. In other words, when ethanol is formed, heat is released to the surroundings as a by-product. The reaction for the formation of ethanol is written below:
<em>C₂H₄ + H₂O → C₂H₅OH</em>
