Answer:
Mass = 2.16 g
Explanation:
Given data:
Number of molecules of F₂ = 3.45 × 10²²
Mass in gram = ?
Solution:
Avogadro number:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole = 6.022 × 10²³ molecules
3.45 × 10²² molecules ×1 mol / 6.022 × 10²³ molecules
0.57× 10⁻¹ mol
0.057 mol
Mass in gram :
Mass = number of moles × molar mass
Mass = 0.057 mol × 37.9 g/mol
Mass = 2.16 g
Answer : If an increase in temperature accompanies a reaction, energy is released. Explanation :In thermodynamics, the reaction is considered as a system and the medium in which the reaction occurs which is usually an aqueous medium is considered as its surrounding. When the heat flows from the system to its surrounding, it increases the temperature of surrounding medium because the heat released by the system is absorbed by its surrounding. This is known as exothermic reaction. An exothermic reaction is always accompanied by energy release. On the other hand, when the heat flows from the surrounding towards system, it decreases the temperature of the surrounding medium. This is known as endothermic reaction. From the above discussion we can say that If an increase in temperature accompanies a reaction, energy is released.
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Answer:
0.0761.
0.0059.
Explanation:
Hello!
In this case, since the writing of numbers in standard notation given the scientific notation requires adding zeros to the left of the first nonzero digit, for the first number, we need to add two zeros as seven is the third digit position:
0.0761.
Next, we need to add three zeros as 5 would be the fourth digit:
0.0059.
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I think sand is just glass and other stuff
<u>Answer:</u> The concentration of sulfate ions in the solution is 0.0522 M
<u>Explanation:</u>
To calculate the the molarity of solution:, we use the equation:

Given mass of alum = 2.17 g
Molar mass of alum = 478.39 g/mol
Volume of solution = 175 mL
Putting values in above equation, we get:

The chemical equation for the ionization of alum follows:

1 mole of alum produces 1 mole of potassium ions, 1 mole of aluminium ions, 2 moles of sulfate ions and 12 moles of water
So, concentration of sulfate ions = 
Hence, the concentration of sulfate ions in the solution is 0.0522 M