Answer:
1.41 moles H2O2(with sig figs)
Explanation:
okay so what is the molar mass of H2O2= (1.008 g/mol)2+(16.00g/mol)2= (2.016+ 32.00) g/ mol
= 34. 02 g/mol
48.0g H2O2* 1 mol H2O2/ 34.02 g H2O2= 1.41 mol H2O2
<h3>Answer:</h3>
The New pressure (750 mmHg) is greater than the original pressure (500 mmHg) hence, the new volume (6.0 mL) is smaller than the original volume (9.0 mL).
<h3>Solution:</h3>
According to Boyle's Law, " <em>The Volume of a given mass of gas at constant temperature is inversely proportional to the applied Pressure</em>". Mathematically, the initial and final states of gas are given as,
P₁ V₁ = P₂ V₂ ----------- (1)
Data Given;
P₁ = 500 mmHg
V₁ = 9.0 mL
P₂ = 750 mmHg
V₂ = ??
Solving equation 1 for V₂,
V₂ = P₁ V₁ / P₂
Putting values,
V₂ = (500 mmHg × 9.0 mL) ÷ 750 mmHg
V₂ = 6.0 mL
<h3>Result:</h3>
The New pressure (750 mmHg) is greater than the original pressure (500 mmHg) hence, the new volume (6.0 mL) is smaller than the original volume (9.0 mL).
Just remember how many electrons can each sublevel hold.
S=2
P=6
D=10
Since we have 10 for atomic number, we can assume we have 10 electrons
1S2
2S2
2P6
The rest have zero because we already have 10 (2+2+6=10)
The molarity of formic acid is 100 mM or 
. The dissociation reaction of formic acid is as follows:
The expression for dissociation constant of the reaction will be:
![K_{a}=\frac{[HCOO^{-}][H^{+}]}{[HCOOH]}](https://tex.z-dn.net/?f=K_%7Ba%7D%3D%5Cfrac%7B%5BHCOO%5E%7B-%7D%5D%5BH%5E%7B%2B%7D%5D%7D%7B%5BHCOOH%5D%7D)
Rearranging,
![[HCOO^{-}]=\frac{K_{a}[HCOOH]}{[H^{+}]}](https://tex.z-dn.net/?f=%5BHCOO%5E%7B-%7D%5D%3D%5Cfrac%7BK_%7Ba%7D%5BHCOOH%5D%7D%7B%5BH%5E%7B%2B%7D%5D%7D)
Here, pH of solution is 4.15 thus, concentration of hydrogen ion will be:
![[H^{+}]=10^{-pH}=10^{-4.15}=7.08\times 10^{-5}M](https://tex.z-dn.net/?f=%5BH%5E%7B%2B%7D%5D%3D10%5E%7B-pH%7D%3D10%5E%7B-4.15%7D%3D7.08%5Ctimes%2010%5E%7B-5%7DM)
Similarly, 
thus,
Putting the values,
![[HCOO^{-}]=\frac{(1.78\times 10^{-4}M)(100\times 10^{-3}M)}{(7.08\times 10^{-5}M}=0.2511 M](https://tex.z-dn.net/?f=%5BHCOO%5E%7B-%7D%5D%3D%5Cfrac%7B%281.78%5Ctimes%2010%5E%7B-4%7DM%29%28100%5Ctimes%2010%5E%7B-3%7DM%29%7D%7B%287.08%5Ctimes%2010%5E%7B-5%7DM%7D%3D0.2511%20M)
Therefore, the concentration of formate will be 0.2511 M.
<h3>
Answer:</h3>
298.15 K
<h3>
Explanation:</h3>
W e are supposed to calculate the Value of K at 25°C
Assuming the value of K represent K, the question wants us to convert degree Celsius to Kelvin.
- To convert degrees Celsius to kelvin scale, we use the relationship;
- Kelvin (K) = Degrees Celsius + 273.15 ; 273.5 is a constant
- That is, to convert temperature from °C to Kelvin we add a constant of 273.15 to the °C given.
In this case;
Temperature is 273.15 °c
Thus, to Kelvin scale temperature will be;
= 25°C + 273.15
= 298.15 K
Therefore, the value of K, at 25°C is 298.15 K
