Answer:
Ka= 3.37×![10^{-9}](https://tex.z-dn.net/?f=10%5E%7B-9%7D)
Explanation:
Ka is the measure of an acid's ability to donate H+ ions. A strong acid will have a larger Ka value. Consider the following equation
HA + H2O → H3O+ + A-
where,
HA is acid, which when dissolves in a solution dissociates into hydronium ion and A- ion. Ka will be represented as
Ka = ![\frac{[H+] [A-]}{[HA]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BH%2B%5D%20%5BA-%5D%7D%7B%5BHA%5D%7D)
Step 1
calculate the number of moles of thiamine hydrochloride
no of moles(n)=g/MM
n=1.00/337.3
n=2.96×![10^{-3}](https://tex.z-dn.net/?f=10%5E%7B-3%7D)
Step 2
The solution was diluted to 10.00ml
∵ 2.96×
/ 0.01 L
=0.296M
Step 3
Find H+ using the formula
pH= -log [H+}
4.50= -log [H+]
[H]= ![10^{-4.50}](https://tex.z-dn.net/?f=10%5E%7B-4.50%7D)
[H]=3.16×![10^{-5}](https://tex.z-dn.net/?f=10%5E%7B-5%7D)
Step 4
Substitude the above values in the formula
Ka=![\frac{[H+] [A-]}{[HA]}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BH%2B%5D%20%5BA-%5D%7D%7B%5BHA%5D%7D)
=![\frac{[0.0000316] [0.000316]}{0.296}](https://tex.z-dn.net/?f=%5Cfrac%7B%5B0.0000316%5D%20%5B0.000316%5D%7D%7B0.296%7D)
= 3.37×![10^{-9}](https://tex.z-dn.net/?f=10%5E%7B-9%7D)
Answer:
3.98g
Explanation:
Given parameters:
Number of molecules = 1.2 x 10²⁴ molecules
Unknown:
Mass of H₂ = ?
Solution:
To find the mass of this molecule, we use the expression below:
Mass = number of moles x molar mass
Molar mass of H₂ = 2(1) = 2g/mol
6.02 x 10²³ molecules are contained in 1 mole of a substance
So; 1.2 x 10²⁴ molecules will have
= 1.99 moles of H₂
Mass of H₂ = 1.99 x 2 = 3.98g
Answer:
14
Explanation:
There are 4 quantum numbers:
<em>n</em>: principal quantum number - describes the electron shell(varies from 1 to 7);
<em>l</em>: azimuthal quantum number - describes the subshell (varies from 0 to 3);
<em>m</em>: magnetic quantum number - describes the specific orbital (varies from -l to +l passing by 0);
<em>s</em>: spin quantum number - describes the spin of the electron (-1/2 or +1/2).
In each orbital (described by m) the maximum number of electrons is 2, so, for subshell 3, the magnetic numbers are -3,-2,-1,0,+1,+2, and +3. So there are 7 orbitals. The maximum number of electrons that can have n=5 and l= 3 is 14.
Answer:
The first molecule Avogadro constant is given as 6.022 X 10∧23/ mol
Explanation: Avogadro constant is the constituent particles of molecules, atoms and ions that make up a mole of an element or compound. Therefore, CO2 comprises one molecule, which is equivalent to 6.022 X 10∧23/ mol.
Because there are 2 Cl on the left, we will put a coefficient 2in front of HCl on the right side to balance out the Cl. This would result in an unequal amount of H, with 6 on the right side and 7 in the left, so we have to put a coefficient of 2 in front of C6H5OH and C6H4OH on both sides to balance out the H. By doing this, we would obtain an equal amount of H on both sides. The Carbon is already balanced, and so is the Oxygen.