We know that the number of moles HCl in 14.3mL of 0.1M HCl can be found by multiplying the volume (in L) by the concentration (in M).
(0.0143L HCl)x(0.1M HCl)=0.00143 moles HCl
Since HCl reacts with KOH in a one to one molar ratio (KOH+HCl⇒H₂O+KCl), the number of moles HCl used to neutralize KOH is the number of moles KOH. Therefore the 25mL solution had to contain 0.00143mol KOH.
To find the mass of KOH in the original mixture you have to divide the number of moles of KOH by the 0.025L to find the molarity of the KOH solution..
(0.00143mol KOH)/(0.025L)=0.0572M KOH
Since the morality does not change when you take some of the solution away, we know that the 250mL solution also had a molarity of 0.0572. That being said you can find the number of moles the mixture had by multiplying 0.0572M KOH by 0.250L to get the number of moles of KOH.
(0.0572M KOH)x(0.250L)=0.0143mol KOH
Now you can find the mass of the KOH by multiplying it by its molar mass of 56.1g/mol.
0.0143molx56.1g/mol=0.802g KOH
Finally you can calulate the percent KOH of the original mixture by dividing the mass of the KOH by 5g.
0.802g/5g=0.1604
the original mixture was 16% KOH
I hope this helps.
Answer: 2. with two symmetrical shells - mirror images of each other.
the term "crinoid" means: 6. phylum where starfish and sea urchins belong
4. lived inside their shells: 1. exoskeletons are made up of this material
7. multicellular organisms that often live in colonies: 8. individuality of coral is called
Explanation:
Crinoid is a term that can be used to describe the radial symmetry of animals that have oral (side of mouth) and aboral surfaces (opposite to the mouth). It is characterized by the mouth at the top surface and surrounded by the arms for feeding it. This is a characteristic feature of animals like star fish and sea urchins and echinoderm animals.
The exoskeleton is a protective shell which protect the animal from the external environment like water, sunlight and predation.
The multicellular organisms that live in the colonies they form coral reef and individually the are called the coral polyp.
Answer:
I. The balloon has a volume of 22.4L
III. The balloon contains 6.022x10^23 molecules.
Explanation:
At stp, it has been proven that 1mole of a gas occupy 22.4L.
Therefore, option (i) is correct.
The molar mass N2 = 14.01 x 2 = 28.02g/mol
Number of mole of N2 = 1 mole
Mass of N2 =..?
Mass = mole x molar Mass
Mass of N2 = 1 x 28.02 = 28.02g.
The mass content of the balloon is 28.02g, therefore, option (ii) is wrong.
From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02x10^23 molecules. This implies that 1 mole of N2 also contains 6.02x10^23 molecules
Therefore, option (iii) is correct.
The correct options to the question are:
Option i and option iii
Answer:
3M
Explanation:
moles ÷ liters = molarity
4.8 ÷ 1.6 = 3M
