Answer:- 0.143 M
Solution:- HCl and NaOH reacts in 1:1 mol ratio as shown in the below reaction:
Let's calculate the initial moles of HCl and the moles of NaOH added to it:
= 0.075 mol HCl
= 0.025 mol NaOH
Since they react in 1:1 mol ratio, 0.025 mol of NaOH will react with 0.025 moles of HCl.
Remaining moles of HCl = 0.075 - 0.025 = 0.050
Total volume of the solution = 0.250 L + 0.100 L = 0.350 L
So, the concentration of HCl in the resulting solution = 
= 0.143 M
Hence, the concentration of HCl acid in the resulting solution is 0.143 M.
Answer : The mass of the water molecule is 4.5 times greater than the mass of the helium atom.
Explanation :
Assumption : The number of water molecules is equal to the number of helium atoms
Given : The mass of water = 4.5 × The mass of helium ........(1)
The mass of Water = Mass of 1 water molecule × Number of water molecule
The mass of Helium = Mass of 1 helium atom × Number of helium atom
Now these two masses expression put in the equation (1), we get
Mass of 1 water molecule × Number of water molecule = 4.5 × Mass of 1 helium atom × Number of helium atom
As per assumption, the number of water molecules is equal to the number of helium atoms. The relation between the mass of water molecule and the mass of helium atom is,
Mass of water molecule = 4.5 × Mass of helium atom
Therefore, the mass of the water molecule is 4.5 times greater than the mass of the helium atom.
<h3>
Answer:</h3>
Gas law : Boyle's law
New pressure: 66.24 atm
<h3>
Explanation:</h3>
Concept tested: Gas laws (Boyle's law)
<u>We are given,</u>
- Initial pressure, P₁ = 2.86 atm
- Initial volume, V₁ = 8472 mL
- New volume, V₂ IS 365.8 mL
We need to determine the new pressure, P₂
- According to Boyle's law , the volume of a fixed mass of a gas and the pressure are inversely proportional at constant temperature.
- That is,
- This means , PV = k (constant)
- Therefore; P₁V₁ = P₂V₂
- Rearranging the formula, we can get the new pressure, P₂
P₂ = P₁V₁ ÷ V₂
= (2.86 atm × 8472 mL) ÷ 365.8 mL
= 66.24 atm
Therefore, the new pressure is 66.24 atm
Answer:
Option (D) freezing point depression
Explanation:
Calcium chloride is added to the roadways after a snowstorm because it reduces the freezing point of the ice. Further more, it has been observed that the calcium chloride also produces enough heat which enhances the melting of the ice as it produces an exothermic reaction.
The answer is statement #3.
