Answer:
Max Planck discovered the quantum of action
Explanation:
Answer:
HF is the limiting reactant
Explanation:
The balanced equation for the reaction is given below:
SiO₂ + 4HF —> SiF₄ + 2H₂O
From the balanced equation above,
1 mole of SiO₂ reacted with 4 moles of HF.
Finally, we shall determine the limiting reactant. This can be obtained as illustrated below:
From the balanced equation above,
1 mole of SiO₂ reacted with 4 moles of HF.
Therefore, 7.5 moles of SiO₂ will react with = 7.5 × 4 = 30 moles of HF.
From the calculation made above, we can see clearly that it will take a higher amount (i.e 30 moles) of HF than what was given from the question (i.e 5 moles) to react completely with 7.5 moles of SiO₂.
Therefore, HF is the limiting reactant and SiO₂ is the excess reactant.
Answer:
Biomass to an Energy source
Explanation:
Researchers have developed a new catalyst that directly converts cellulose, the most common form of biomass, into ethylene glycol, an important intermediate product for chemical industry. Alternatives to fossil fuels and natural gas as carbon sources and fuel are in demand.
Answer:
The minimum concentration of Cl⁻ that produces precipitation is 12.6M
Explanation:
The Ksp of PbCl₂ is expressed as:
PbCl₂(s) → Pb²⁺(aq) + 2Cl⁻(aq)
The Ksp is:
Ksp = 1.6 = [Pb²⁺] [Cl⁻]²
When Ksp = [Pb²⁺] [Cl⁻]² the solution begind precipiration.
A 0.010M Pb(NO₃)₂ is 0.010M Pb²⁺, thus:
1.6 = [0.010M] [Cl⁻]²
160 = [Cl⁻]²
12.6M = [Cl⁻]
<h3>The minimum concentration of Cl⁻ that produces precipitation is 12.6M</h3>
