Answer:
a) 0.2118 mol of I₂ is produced.
b) 49.93 g of I₂ is produced.
Explanation:
a) The balanced equation shows that to produce 1 mol of I₂ we need 2 mol of CuCl₂ . Therefore, the amount of I₂ produced will always be half the amount of CuCl₂ given.
b) In order to calculate the mass of I₂ produced we need to know its molar mass:
Each mole of I₂ weighs 253.8 g, therefore MM = 253.8 g/mol.
4 moles of NaCl is produced from 2 moles of Na₂CrO₄.
<u>Explanation:</u>
Given reaction is
PbCl₂(aq) + Na₂CrO₄(aq)→ PbCrO₄(s) + 2 NaCl (aq)
It is the balanced equation which means that on both sides of the equation, number of atoms of each element are equal.
From the above balanced equation it says that molar ratio of Na₂CrO₄ to NaCl is 1 : 2.
That is 1 mole of Na₂CrO₄ produces 2 moles of NaCl, so the molar ratio is 1:2.
2 moles of Na₂CrO₄ produces 4 moles of NaCl.
So the molar ratio of Na₂CrO₄ to NaCl is 2: 4.
The final temperature is -138 °C.
Explanation:
Using the equation of specific heat
We can easily find the final temperature of a 73.174 g of copper sample. As we know that specific heat is the amount of energy required to raise the temperature of the object to 1°C.
The specific heat of copper is known as 0.387 J/g°C and the initial temperature is said as 102 °C . The mass is given as 73.174 g. The heat released is 6800 J.
Since the heat is released the Q value will be negative.
Thus, the final temperature is -138 °C.
The most brittle one is selenium!