The initial mass of sodium hydroxide is 3.3 g (answer C)
<u><em>calculation</em></u>
Step 1 : find the moles of iron (ii) hydroxide ( Fe(OH)₂
moles = mass÷ molar mass
from periodic table the molar mass of Fe(OH)₂ = 56 + [16 +1]2 = 90 g/mol
moles is therefore = 3.70 g÷ 90 g/mol = 0.041 moles
Step 2: use the mole ratio to calculate the moles of sodium hydroxide (NaOH)
from given equation NaOH : Fe(OH)₂ is 2 :1
therefore the moles of NaOH = 0.041 x 2 = 0.082 moles
Step 3: find mass of NaOH
mass = moles x molar mass
from the periodic table the molar mass of NaOH = 23 +16 +1 = 40 g/mol
mass = 0.082 moles x 40 g/mol = 3.3 g ( answer C)
The resulting pressure of the gas after decreasing the initial volume from 2 L to 1 L is 3 atm.
<h3>What is
Boyle's Law?</h3>
According to the Boyle's Law at constant temperature, pressure of the gas is inversely proportional to the volume of that gas.
For the given question we use the below equation is:
P₁V₁ = P₂V₂, where
P₁ = initial pressure of gas = 1.5 atm
V₁ = initial volume of gas = 2 L
P₂ = final pressure of gas = ?
V₂ = final volume of gas = 1 L
On putting all these values on the above equation, we get
P₂ = (1.5atm)(2L) / (1L) = 3 atm
Hence required pressure of the gas is 3 atm.
To know more about Boyle's Law, visit the below link:
brainly.com/question/469270
Answer:
1, just I) color.
Explanation:
Physical properties are the properties that can be observed without changing the composition of a substance, such as color, temperature, density, and boiling point.
A physical change is a change in the substance that only modifies its aggregation state, such as solidification, and boiling.
Chemical properties are the properties that need a reaction to being observed, such as the combustibility, which needs a combustion reaction to being quantified.
When a chemical reaction occurs, and the composition of the substance change, it's a chemical change.
So, the heating copper with carbon is a chemical reaction, and purification by electrolysis is too. Color is the only physical property.
Answer:
2.12 moles of gas were added.
Explanation:
We can solve this problem by using<em> Avogadro's law</em>, which states that at constant temperature and pressure:
Where in this case:
We <u>input the data</u>:
- 6.13 L * n₂ = 11.3 L * 2.51 mol
As <em>4.63 moles is the final number of moles</em>, the number of moles added is: