To find the mass of reagent to be added in the reaction, we need to determine the pH of the buffer. Using the following equation
pH= pKa + log ([NH3] / [NH4+])
= 9.26 + LOG ( 0.3 / 0.3)
= 9.26
[h+]= 5.5x10^-10 M, you need to increase that concentration for a ph of 8.6, [H+] needs to be 2.51x10^-9M
2.51x10^-9 moles - 5.5x10^10 moles = 1.96x10^-9 moles
1.96x10^-9 x 36.45g/mole = 7.14x10^-8 g
So the mass of HCI that you should add to the reaction is 7.14x10^-8 g
Answer: 498.51mmHg
Explanation:
First let us analyse what was given from the question:
T1 = 425K
T2 = 275.15K
P1 = 770 mmHg
P2 =?
Using the general gas equation
P1V1/T1 = P2V2/T2
But we were told from the question that the volume is constant. So, our equation becomes:
P1/T1 = P2/T2
770/425 = P2 /275.15
Cross multiply to express in linear form:
P2 x 425 = 770 x 275.15
Divide both side by 425, we have:
P2 = (770 x 275.15) /425
P2 = 498.51mmHg
The equation for finding how many moles are in a substance is
moles = mass / relative formula mass,
where mass is measured in g.
The r.f.m. (relative formula mass) is found by adding together all of the atomic masses of the elements in a substance.
e.g. CO2 (carbon dioxide) has 1 atom of carbon and two atoms of oxygen.
The relative atomic mass of carbon is approximately 12.
The relative atomic mass of oxygen is approximately 16.
12 + (2 x 16) = 44
The r.f.m. of carbon dioxide is 44.
You would then divide the mass of the substance (how much there is of it) by its r.f.m. to find the mole number.
Answer:
they combine to form metal oxide
Answer:
The coefficient for PH3 is 8. Option D is correct.
Explanation:
Step 1: The unbalanced equation
P2H4(g) ⇆ PH3(g) + P4(s)
Step 2: Balancing the equation
P2H4(g) ⇆ PH3(g) + P4(s)
On the left side we have 4x H (in P2H4), on the right side we have 3x H (in PH3). To balance the amount of H on both sides, we have to multiply P2H4 on the left side by 3 and PH3 on the right by 4.
3P2H4(g
) ⇆ 4PH3(g) + P4(s)
On the left side we have 6x P (in 3P2H4) on the right side we have 8x P (4x in 4PH3 and 4x in P4). To balance the amount of P on bot hsides, we have to multiply 3P2H4 by 2 and 4PH3 also by 2. Now the equation is balanced
6P2H4(g
) ⇆ 8PH3(g) + P4(s)
The coefficient for PH3 is 8. Option D is correct.
