1.26 x 10²⁴particles
Explanation:
Given parameters:
Number of moles of the compound = 2.1 moles
Unknown:
Number of particles contained in the compound = ?
Solution:
A mole can be defined as the amount of a substance that contains Avogadro's number of particles 6.02 x 10²³.
The particles mentioned here can be atoms, molecules, formula units, ions, electrons, protons, neutrons and so forth.
To solve for the number of moles:
Number of particles = number of moles x 6.02 x 10²³
Number of particles = 2.1 x 6.02 x 10²³ = 12.64 x 10²³ = 1.26 x 10²⁴particles
Learn more:
mole calculation brainly.com/question/1841136
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We will assume that the only reactants are x and y and that the only product is xy.
Based on the law of mass conservation, mass is an isolated system that can neither be created nor destroyed.
Applying this concept to the chemical reaction, we will find that the total mass of the reactants must be equal to the total mass of the products,
therefore:
mass of x + mass of y = mass of xy
12.2 + mass of y = 78.9
mass of y = 78.9 - 12.2 = 66.7 grams
<span> rate 3/1= square root of 32/x
square both sides
9/1=32x
x = 32/9
= 3.6
Must be He
molar mass =4
</span>
Answer:- 
Solution:- It is a volume unit conversion problem where we are asked to convert the volume from
to microliters.
We know that:
= 1 mL

and, 
Let's use these conversions factors for the desired conversion using dimensional as:

= 
So, the answer is
.
Answer: 100.
Explanation:
1) The subscripts to the right of each element (symbol) in the chemical formula tells the number of atoms of that element present in one unit formula.
2) The unit formula of C₄H₄S₂ is equal to 1 molecule.
3) Therefore, there are 4 carbon atoms, 4 hydrogen atoms and 2 sulfur atoms in each molecule of C₄H₄S₂.
4) Then, you just have to multiply the corresponding subscript of the element times the number of molecules (25 in this case) to find the number of atoms of that kind.
5) These are the calculations for each element in the molecule C₄H₄S₂.
i) C: 4 × 25 = 100
ii) H: 4 × 25 = 100
iii) S: 2 × 25 = 50.
6) The question is about H only, so the answer is that there are 100 hydrogen atoms in 25 molecules of C₄H₄S₂.