Answer:
0.302 moles
Explanation:
Data given
Mass of Pb(NO₃)₂ = 100 g
Moles of Pb(NO₃)₂ = ?
Solution:
To find mole we have to know about molar mass of Pb(NO₃)₂
So,
Molar mass of Pb(NO₃)₂ = 207 + 2[14 + 3(16)]
= 207 + 2[14 + 48]
= 207 + 124
Molar mass of Pb(NO₃)₂ = 331 g/mol
Formula used :
no. of moles = mass in grams / molar mass
Put values in above formula
no. of moles = 100 g / 331 g/mol
no. of moles = 0.302 moles
no. of moles of Pb(NO₃)₂ = 0.302 moles
<h2>The answer is option b "free energy is zero"</h2>
Explanation
- The reaction that has negative free energy are called exergonic reactions that means the reactants have more free energy than the product formed.
- The reaction that has positive free energy are called endergonic reactions that means the final state or the products formed have more free energy than the initial state or the reactants.
- The reaction that has zero free energy occurs when the free energy of both reactants and the products are same hence the rate of formation of products and reactants are equal.
- Therefore, when reactants and products are being formed at an equal rate the free energy is zero.
It will melt
This is because the molecules in the metal begin to move faster and faster turning from solid to liquid
Energy and the nature of the current