Answer:
<em>3.27·10²³ atoms of O</em>
Explanation:
To figure out the amount of oxygen atoms in this sample, we must first evaluate the sample.
The chemical formula for sodium sulfate is <em>Na₂SO₄, </em>and its molar mass is approximately 142.05
.
We will use stoichiometry to convert from our mass of <em>Na₂SO₄ </em>to moles of <em>Na₂SO₄</em>, and then from moles of <em>Na₂SO₄ </em>to moles of <em>O </em>using the mole ratio; then finally, we will convert from moles of <em>O </em>to atoms of <em>O </em>using Avogadro's constant.
19.3g <em>Na₂SO₄</em> · 
· 
·
After doing the math for this dimensional analysis, you should get a quantity of approximately <em>3.27·10²³ atoms of O</em>.
Following reaction is involved in present system:
2KMnO4 + 5H2O2 + 3H2SO4 → 2MnSO4 + K2SO4 + 5O2 + 8H2O
From the above balance reaction, it can be seen that 2 moles of KMnO4 is consumed for every 5 moles of H2O2.
Now, percent by mass of hydrogen peroxide in the original solution can be estimated as follows:
percent by mass =
∴percent by mass =
= 4 %
Answer:
Explanation:
In 150 ml of .06 g / ml solution , gram of iodine = 150 x .06 g = 9 g
Let volume of given concentration of .12 g / ml required be V
In volume V , gram of iodine = V x .12 g
According to question
V x .12 = 9 g
V = 9 / .12 = 75 ml
So, 75 ml of .12 g/ml will be taken and it is diluted to the volume of 150 ml to get the solution of required concentration .
Answer:
Carbon=5, hydrogen=12, oxygen=16
Explanation:
Carbon=5, hydrogen=12, oxygen=16
In order to effectively count the number of atoms, we look at the equation closely and take note of the stoichiometric coefficients of each reactant as this influences the number of atoms of that element present.
For instance, oxygen is diatomic and has a stoichiometric coefficient of 8. This implies the there are sixteen atoms of oxygen altogether.
Note that the left hand side refers to the reactants side.
Answer:
Mole fraction of nitrogen = 0.52
Explanation:
Given data:
Temperature = 31.2 °C
Pressure = 870.2 mmHg
Volume = 15.1 L
Mass of mixture = 24.1 g
Mole fraction of nitrogen = ?
Solution:
Pressure conversion:
870.2 /760 = 1.12 atm
Temperature conversion:
31.2 + 273 = 304.2 K
Total number of moles:
PV = nRT
n = PV/RT
n = 1.12 atm × 15.1 L / 0.0821 L.atm. mol⁻¹.K⁻¹ × 304.2 K
n = 16.9 L.atm. /25 L.atm. mol⁻¹
n = 0.676 mol
Number of moles of nitrogen are = x
Then the number of moles of CO₂ = 0.676 - x
Mass of nitrogen = x mol . 28 g/mol and for CO₂ Mass = 44 g/mol ( 0.676 - x)
24.1 = 28x + ( 29.7 -44x)
24.1 - 29.7 = 28x - 44x
-5.6 = -16 x
x = 0.35
Mole fraction of nitrogen:
Mole fraction of nitrogen = moles of nitrogen / total number of moles
Mole fraction of nitrogen = 0.35 mol / 0.676 mol
Mole fraction of nitrogen = 0.52
