The answer to this would be helium
<h3>
Answer:</h3>
= 5.79 × 10^19 molecules
<h3>
Explanation:</h3>
The molar mass of the compound is 312 g/mol
Mass of the compound is 30.0 mg equivalent to 0.030 g (1 g = 1000 mg)
We are required to calculate the number of molecules present
We will use the following steps;
<h3>Step 1: Calculate the number of moles of the compound </h3>
Therefore;
Moles of the compound will be;
= 9.615 × 10⁻5 mole
<h3>Step 2: Calculate the number of molecules present </h3>
Using the Avogadro's constant, 6.022 × 10^23
1 mole of a compound contains 6.022 × 10^23 molecules
Therefore;
9.615 × 10⁻5 moles of the compound will have ;
= 9.615 × 10⁻5 moles × 6.022 × 10^23 molecules
= 5.79 × 10^19 molecules
Therefore the compound contains 5.79 × 10^19 molecules
Answer:
Molarity of solution is 1.10x10⁻³ M
Explanation:
Solute NaOCl
7.4% by mass means, that in 100 grams of solution, we have 7.4 g of solute.
Molar mass of NaOCl = 74.45 g/m
Mol = Mass / Molar mass
7.4 g / 74.45 g/m = 0.099 moles
Density of solution = 1.12 g/mL
Density = Mass / volume
1.12g/mL = 100 g / volume
Volume = 100 g / 1.12g/mL = 89.3 mL
Molarity = mol /L
89.3 mL = 0.0893 L
0.099 moles / 0.0893 L = 1.10x10⁻³ M
Answer:
C) Chemical changes involve formation of a new substance while physical change only impacts appearance or form.
Explanation:
The obvious difference between a chemical change and physical change is that in a chemical change new substances are produced while in a physical change, the form of the compounds are altered.
- Most phase changes are products of physical changes. Such changes are easily reversible.
- In a chemical change, a new kind of matter is formed. It is accompanied by energy changes.
- The process is not easily reversible.
Water isn't being produced all around us because the hydrogen and oxygen are present in stable form.
<h3>How come water isn't being produced all around us?</h3>
Water molecule is produced when the unstable hydrogen reacts with unstable oxygen because they are very reactive. Due to their reactive nature, hydrogen and oxygen react with each other forming water molecule. So that's why we can say that water is not being produced around us due to stable form of hydrogen and oxygen.
So we can conclude that Water isn't being produced all around us because the hydrogen and oxygen are present in stable form.
Learn more about water here: brainly.com/question/1313076
#SPJ1
