The number of protons is equal to the atomic number of every element in the periodic table.
Example: The atomic number of Niobium (Nb) is 41. Therefore, the number of protons is also 41.
Answer: Prophase.
In prophase, chromosomes condense and become visible. Spindle fibers emerge from the centrosomes.
Answer:
1 mole of aluminum must contain 6.022⋅1023 atoms of aluminium → this is known as Avogadro's constant.
Explanation:
First, we write the balanced equation for this reaction:
2KI + Pb(NO₃)₂ → 2KNO₃ + PbI₂
From this equation, we see that there are 2 moles of potassium iodide required for each mole of lead (II) nitrate. Moreover, we may use the formula:
Moles = volume (in L) * molarity
We find the molar relation ship for KI : Pb(NO₃)₂ to be 2 : 1. So:
M₁V₁ = 2M₂V₂
V₁ = 2M₂V₂/M₁
V₁ = 2 * 0.112 * 0.155 / 0.2
V₁ = 0.1736 L
The volume required is 173.6 mL
