Tests for gases
Hydrogen, oxygen, carbon dioxide, ammonia and chlorine can be identified using different tests.
Hydrogen. A lighted wooden splint makes a popping sound in a test tube of hydrogen.
Oxygen. A glowing wooden splint relights in a test tube of oxygen.
Answer:
no. of moles of PbI₂ = 14 moles
Explanation:
Data Given:
no. of moles of HI = 28 moles
no. of moles of Pbl₂ = ?
Reaction Given
Pb + 2HI -------→ Pbl₂ + H₂
Solution:
To solve this problem we have to look at the reaction
Reaction:
Pb + 2HI -------→ Pbl₂ + H₂
2 mol 1 mol
So if we look at the reaction 2 mole of hydrogen iodide (HI) gives 1 moles of Lead iodide (PbI₂), then how many moles of Lead iodide (PbI₂) will be produced by 28 moles of hydrogen iodide (HI)
For this apply unity formula
2 mole of HI ≅ 1 moles of PbI₂
28 mole of HI ≅ X moles of PbI₂
By Doing cross multiplication
moles of PbI₂ = 28 moles x 1 moles / 2 mole
moles of PbI₂ = 14 mole
28 mole of HI will produce 14 moles of PbI₂
Answer:
C. some substances can move freely across the cell membrane, while others must be transported.
Explanation:
Warm air rises, cool falls. (a)
