Answer:
5.25g
Explanation:
We'll begin by writing the balanced equation for the reaction. This is shown below:
Na2SiO3 + 8HF → H2SiF6 + 2NaF + 3H2O
From the balanced equation above,
8 moles of HF reacted to produce 2 moles of NaF.
Therefore, 0.5 moles of HF will react to produce = (0.5 x 2)/8 = 0.125 mole of NaF.
Next, we shall convert 0.125 mole of NaF to grams.
This is illustrated below:
Mole of NaF = 0.125 mole
Molar mass of NaF = 23 + 19 = 42g/mol
Mass of NaF =..?
Mass = mole x molar mass
Mass of NaF = 0.125 x 42
Mass of NaF = 5.25g
Therefore, 5.25g of NaF is produced from the reaction.
Answer:
1) pure water
2) 0.75 m CaCl2
3) 1.0 m NaCl
4) 0.5 m KBr
5) 1.5 m glucose (C6H12O6)
Explanation:
Boiling point elevation is a colligative property. Coligative properties are properties that depend on the amount of solute present in the system. The boiling point of solvents increase due to the presence of solutes.
The boiling point elevation depends on the number of particles the solute forms in solution and the molality of the solute. The more the number of particles formed by the solute and the greater the molality of the solute, the greater the magnitude of boiling point elevation.
The order of decreasing hoping point elevation is;
1) 0.75 m CaCl2
2) 1.0 m NaCl
3) 0.5 m KBr
4) 1.5 m glucose (C6H12O6)
Answer: % error of observation is 4.77%
Explanation:
Given:
Observation value = 415nm
theoretical value= 435.8nm
Percent error of observation = theoretical value- observation value/ theoretical value x 100 %
= 435.8-415/435.8= 0.04772 x 100 = 4.77%
therefore % error of observation is 4.77%
Answer:
3m/s
Explanation:
Data obtained from the question include:
Initial speed (s1) = 4 m/s
Final speed (S2) = 7m/s
Change in speed (ΔS)
ΔS = s2 — s1
ΔS = 7 — 4
ΔS = 3m/s
Therefore, the change in speed is 3m/s
I assume you’re looking for a balanced equation.
SiCl4 + 2H2O = SiO2 + 4HCl
