Answer: Option (b) is the correct answer.
Explanation:
When there are more number of hydroxide ions in a solution then there will be high concentration of 
or hydroxide ions. As a result, more will be the strength of base in that particular solution.
A base is strong when it readily dissociate into its ions in the solution. When a base is strong, then it does not matter at what concentration it is dissolved in the solution because despite of its low concentration it will remain a strong base.
Thus, we can conclude that out of the given options, the statement even at low concentrations, a strong base is strong best relates the strength and concentration of a base.
Answer: 
Explanation:
Given : Sample size : n= 30 , it means it is a large sample (n≥ 30), so we use z-test .
Significance level : 
Critical value: 
Sample mean : 
Standard deviation : 
The formula to find the confidence interval is given by :-
i.e. 
i.e. 
Hence, the 95% confidence interval for the mean mpg in the entire population of that car model =
Answer:
Number of moles of methane form = 2.3 mol
Explanation:
Given data:
Number of moles of Hydrogen = 4.6 mol
Number of moles of methane form = ?
Solution:
Chemical equation:
C + 2H₂ → CH₄
Now we will compare the moles of methane with hydrogen from balance chemical equation.
H₂ : CH₄
2 : 1
4.6 : 1/2×4.6 = 2.3 mol
Form 3.6 moles of hydrogen 2.3 moles of methane can be formed.
A combustion reaction of an will generally produce CO2 and H20 -- carbon dioxide and water and/or an oxide
looking at the combustion material C2H2, you know that the end products will be CO2 and H20, so the question is how much of each will you get
well, look at the total amount of carbon atoms, 2 C2, which means a total of 4 carbon atoms in this reaction, since only CO2 has carbon atoms, that means there must be 4 CO2 as an end product and 4 CO2 will use up 4 of 5 O2 molecule leaving only 1 O2 molecule for the H2 reaction.
now O2 has a total of 2 oxygen molecules whereas H20 has only a single oxygen molecule, hence the end product must have 2 H20
check that the H atoms balance out on both sides
Answer:
480.6 g
Explanation:
Given data:
Number of molecules of methanol = 9.01 ×10²⁴
Mass in gram = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
9.01 ×10²⁴molecules ×1 mol /6.022 × 10²³ molecules
1.5 ×10¹ mol
15 mol
Mass in gram:
Mass = number of moles × molar mass
Mass = 15 mol × 32.04 g/mol
Mass = 480.6 g
