Answer:
True
Explanation:
when a physical change occurs in a substance, the appearance might change but the chemical identity remains same. For example, if liquid water is heated, the water changes to gaseous form .This means the appearance of the water has changed, but the chemical identity remains same as both liquid water and steam has both oxygen and hydrogen as the component molecules or atoms.
Answer:
5.12 molecules of Ag₂S could be produced from 10 molecules of silver.
Explanation:
Given data:
Molecules of Ag = 10 molecules
Molecules of Ag₂S = ?
Solution:
First of all we will convert the number of molecules into gram.
10/ 6.022 ×10²³ = 1.7 × 10⁻²³ mol
Mass of Ag:
Number of moles = mass/ molar mass
Mass = Number of moles × molar mass
Mass = 1.7 × 10⁻²³ mol × 107.9 g/mol
Mass = 183.43 × 10⁻²³ g
Chemical equation:
2Ag + H₂S → Ag₂S + H₂
Now we will compare the moles of silver with Ag₂S from balanced chemical equation.
Ag : Ag₂S
2 : 1
1.7 × 10⁻²³ : 1/2 ×1.7 × 10⁻²³ = 0.85 × 10⁻²³ mol
Molecules of Ag₂S:
0.85 × 10⁻²³ × 6.022 ×10²³ = 5.12 molecules
Answer: 17.5
explanation: multiply 3.5 by 5 and you will get 17.5
When something burns it usually means something is being damaged or being changed such as colour, smell, or shape.
Answer:
When dry ice is exposed to warm air, a gas called carbon dioxide is produced through a process called sublimation
Explanation: