Answer:
option C = 9.0 x 10²³ atoms
Explanation:
Data Given:
no. of moles of tin (Sn) atoms = 1.5 moles
no. of tin (Sn) atoms = ?
Solution:
Formula used to find number of atoms
no. of moles = no. of atoms / Avogadro's number
Rearrange the above equation:
no. of atoms = no. of moles x Avogadro's number . . . . . . (1)
Where
Avogadro's number = 6.022 x 10²³
Put values in equation 1
no. of atoms = 1.5 x 6.022 x 10²³
no. of atoms = 9.033 x 10²³
Round the figure = 9.0 x 10²³ atoms
So option C is correct
Answer:
The energy released will be -94.56 kJ or -94.6 kJ.
Explanation:
The molar mass of methane is 16g/mol
The given reaction is:
the enthalpy of reaction is given as ΔH = -890.0 kJ
This means that when one mole of methane undergoes combustion it gives this much of energy.
Now as given that the amount of methane combusted = 1.70g
The energy released will be:
<u>Given information:</u>
A solution with a high H+ ion concentration
<u>To determine:</u>
The nature of pH of such a solution
<u>Explanation:</u>
pH is a measure of the H+ ion concentration in a given solution. Lower the pH higher will be the H+ concentration and the solution is termed acidic. In contrast, if the pH is higher the H+ concentration will be lower and the solution is basic.
Mathematically,
pH = -log[H+]
[H+] =
pH = 2; [H+] = 10⁻²M
pH = 7; [H+] = 10⁻⁷M
pH = 13; [H+] = 10⁻¹³M
pH = 14; [H+] = 10⁻¹⁴M
Ans: (a)
Thus, the highest concentration of H+ ions is for a solution of pH = 2
2.00x10^23 x 1 mol/6.02x10^23 molecules x 279.25g C10H15O9/1 mol
= 92.77 grams
Molar mass of C10H15O9 is 279.25 grams.
So the answer is 92.77 grams
Answer:
0.231 mol/L
Explanation:
The first step is to write the balanced equation for this reaction:
The second step is to find the number of moles in the acid:
number of moles = volume * concentration
= 0.035 L * 0.275 mol/L
= 0.009625 mol
The third step is to use the molar ratio from the balanced chemical equation to find the number of moles of NaOH that can neutralize 0.009625 mol of sulphuric acid.
n(sulphuric acid) : n(sodium hydroxide)
1 : 2
0.009625 mol : x
x = 0.01925 mol
Fourth step is to calculate the concentration of sodium hydroxide: