The systematic name of Mg(NO3)2 is magnesium nitrate. If you were confused, there are two of the nitrate because magnesium has a charge of 2+ while just one nitrate has a 1- charge. They would have to cancel out because it is an ionic compound.
Answer:
n₂ = 0.2 mol
Explanation:
Given data:
Volume of 1st balloon = 2.5 L
Moles of He in 1st balloon = 0.100 mol
Volume of second balloon = 5.0 L
Moles in second balloon = ?
Solution:
According to the Avogadro law,
Number of moles of gas is directly proportional to the volume of gas at constant temperature and pressure.
Mathematical expression:
V₁/n₁ = V₂/n₂
V₁ = Volume of 1st balloon
n₁ = Moles of He in 1st balloon
V₂ = Volume of second balloon
n₂ = Moles in second balloon
Now we will put the values.
2.5 L / 0.100 mol = 5 L /n₂
n₂ = 5 L× 0.100 mol /2.5 L
n₂ = 0.5 mol /2.5
n₂ = 0.2 mol
Answer:-
A) 3.745
B) 2 x 10^-13 M
[H+]
pOH = 1.3
Explanation:-
A) From the question we see
The strength of HCl solution = 1.8 x 10^-4 M.
The M stands for molarity which is moles / Litre.
HCl is a monobasic acid. So the number of moles of Hydrogen ion H+ HCl can give is the same as the value of it’s strength in moles per litre.
The hydrogen ion concentration [H+] is therefore 1.8 x 10^-4.
The formula for pH is
pH = - log [ H+ ]
= - log [1.8 x 10^-4]
= 3.745
B) From the question we see
The strength of KOH = 0.05 M
The M stands for molarity which is moles / Litre.
KOH is a monoacidic base. So the number of moles of Hydroxyl ion OH- KOH can give is the same as the value of it’s strength in moles per litre.
The Hydroxyl ion concentration [OH-] is therefore 0.05
The relation between [OH-] and [H+] is
[H+] x [ OH-] = 10^-14
[H+] = 10^-14 / [OH-]
= 10^-14/ 0.05
= 2 x 10^-13 M
Using the relation between pH and [OH-]
pOH = - log [OH-]
= -log [0.05]
= 1.3
Answer:
Method 1 - precision
Method 2 - accuracy
Method 3 - precision
Method 4 - accuracy
Explanation:
The accuracy of a method refers to how close the experimental result is to the accepted value. Accuracy could be checked by carrying out the required test on the standard and not on the sample or by adding a known amount of analyte to the sample so that the results obtained can be carefully compared.
Precision on the other hand, refers to how close the results of a replicate analysis are to each other. In testing for precision, the analysis must be carried out several times, in order to check how close the results are to each other.
