Answer:
the water displaced will not help the student find the correct volume because you can not accurately calculate it. you have to get the water when it is settled then you place the wood in.
Explanation:
Answer:
1. All matter is composed of atoms. Atoms cannot be destroyed or created.
2. All atoms of different elements are different in properties.
3. All atoms of the same element are identical in properties.
4. During a chemical reaction, no atoms are created or destroyed. The atoms are rearranged.
5. Compounds are formed by the combination of two different atoms with same ratio.
Answer:
71.372 g or 0.7 moles
Explanation:
We are given;
- Moles of Aluminium is 1.40 mol
- Moles of Oxygen 1.35 mol
We are required to determine the theoretical yield of Aluminium oxide
The equation for the reaction between Aluminium and Oxygen is given by;
4Al(s) + 3O₂(g) → 2Al₂O₃(s)
From the equation 4 moles Al reacts with 3 moles of oxygen to yield 2 moles of Aluminium oxide.
Therefore;
1.4 moles of Al will require 1.05 moles (1.4 × 3/4) of oxygen
1.35 moles of Oxygen will require 1.8 moles (1.35 × 4/3) of Aluminium
Therefore, Aluminium is the rate limiting reagent in the reaction while Oxygen is the excess reactant.
4 moles of aluminium reacts to generate 2 moles aluminium oxide.
Therefore;
Mole ratio Al : Al₂O₃ is 4 : 2
Thus;
Moles of Al₂O₃ = Moles of Al × 0.5
= 1.4 moles × 0.5
= 0.7 moles
But; 1 mole of Al₂O₃ = 101.96 g/mol
Thus;
Theoretical mass of Al₂O₃ = 0.7 moles × 101.96 g/mol
= 71.372 g
The moles of nitrogen in 0.30 mole of caffeine is calculated as follows
write the chemical formula = C8H10N4O2
for this case from the chemical formula we have 4 atoms of nitrogen in caffeine
therefore moles of nitrogen in caffeine = 4 x0.30 =1.2 moles
Answer:
2Na + F2 → 2NaF
Explanation:
A balanced equation is an equation in which the number of the individual atoms on the left side is the same with that on the right side of the equation. This is true as explained by the law of conservation of matter.
From the options above only the equation given below is balanced :
2Na + F2 → 2NaF
There are 2 atoms of Na both on the left and on the right. There are also 2 atoms of F both on the left and right side