Answer:
3.01×10²⁴ molecules of H₂
Explanation:
Reaction that can produce hydrogen gas from Pb can be this:
Pb + H₂S → PbS + H₂
1 mol of Pb can react to 1 mol of H₂S to produce 1 mol of PbS and 1 mol of H₂
Ratio is always 1:1.
In conclussion 5 moles of lead will produce 5 moles of H₂.
Let's apply the NA to count molecules
1 mol contains 6.02×10²³
Then, 5 moles must contain (5 . 6.02×10²³) = 3.01×10²⁴ molecules
Combination or Synthesis Reaction. A combination of synthesis reaction is one. where a new product is synthesized by combination of two or three reactants.
Decomposition Reaction
Displacement or Replacement Reaction
Acid Base Reaction
Combustion Reaction
Answer:
Electrical conductivity in metals is a result of the movement of electrically charged particles. Because valence electrons are free to move, they can travel through the lattice that forms the physical structure of a metal.
Explanation:
Calories is a unit of energy, so we need to calculate the energy or heat absorbed or released by the system. We use the equation:
U = mCpΔT
where:
m = mass of material
Cp = specific heat capacity of material
ΔT = (Tf - Ti) = temperature change
First, you must look for the specific heat capacity of copper. You can use any chemistry or engineering book or website. According to Engineering Toolbox, the specific heat capacity of copper is 0.09 cal/(g-°C).
U = 200(0.09)(33-28) = 90 calories
Since the value is positive, energy is absorbed.