Answer:
Number 6
Explanation:
A reflex action is an involuntary action and nearly instantaneous movement in response to a stimulus.
Answer : The molarity of solution is, 1.73 mole/L
Explanation :
The relation between the molarity, molality and the density of the solution is,
where,
![d=M[\frac{1}{m}+\frac{M_b}{1000}]](https://tex.z-dn.net/?f=d%3DM%5B%5Cfrac%7B1%7D%7Bm%7D%2B%5Cfrac%7BM_b%7D%7B1000%7D%5D)
d = density of solution = 
m = molality of solution = 2.41 mol/kg
M = molarity of solution = ?
= molar mass of solute (toluene) = 92 g/mole
Now put all the given values in the above formula, we get the molality of the solution.
![0.876g/ml=M\times [\frac{1}{2.41mol/kg}+\frac{92g/mole}{1000}]](https://tex.z-dn.net/?f=0.876g%2Fml%3DM%5Ctimes%20%5B%5Cfrac%7B1%7D%7B2.41mol%2Fkg%7D%2B%5Cfrac%7B92g%2Fmole%7D%7B1000%7D%5D)
Therefore, the molarity of solution is, 1.73 mole/L
Answer:
The process in which energy is emitted by one object ,transmitted through .......
Answer:
Na₂CO₃ · 10H₂O
Explanation:
The formula for sodium carbonate hydrate is:
Na₂CO₃ · xH₂O
The unknown "x" is the number of water molecules contained in the hydrate.
To find "x" we have to use the hydrogen percentage in the sample, 7.05 % H.
First we calculate the molecular weight of Na₂CO₃ · xH₂O:
molecular weight of Na₂CO₃ · xH₂O = 23 × 2 + 12 + 16 × 3 + 18x
molecular weight of Na₂CO₃ · xH₂O = 106 + 18x g/mole
Now we devise the fallowing reasoning tanking in account 1 mole of Na₂CO₃ · xH₂O:
if in 106 + 18x grams of Na₂CO₃ · xH₂O we have 2x grams of hydrogen
then in 100 grams of Na₂CO₃ · xH₂O we have 7.05 grams of hydrogen
106 + 18x = (100 × 2x) / 7.05
106 + 18x = 28.4x
106 = 28.4x - 18x
106 = 10.4x
x = 106 / 10.4
x = 10.2 ≈ 10
The formula for the washing soda is Na₂CO₃ · 10H₂O.
Answer:
Number of moles = mass/molar mass
Explanation:
Given data:
mass of Al = 11 g
Moles = ?
Solution:
Formula:
Number of moles = mass/molar mass
Molar mass of aluminium is 27 g/mol
Now we will put the values in formula.
Number of moles = 11 g/ 27 g/mol
Number of moles = 0.41
The number of moles in 11 g Al are 0.41 mol.
