Answer:
punctuation, and if it makes sense
Sedimentary rocks form layers.
Answer:
Higher concentration to an area of lower concentration
Explanation:
When you open a perfume bottle at a corner of a room, after a while, its fragrance can be perceived across a distance at the other end of the room. This is because, molecules of the compound in the fragrance have moved from the area of higher concentration in the perfume bottle, across a concentration gradient to a region of lower concentration at the other end of the room. This is diffusion.
Answer:
Mass of hydrogen produced = 2.1 g
Mass of excess reactant left = 25.2 g
Explanation:
Given data:
Mass of Mg = 50.0 g
Mass of HCl = 75.0 g
Mass of hydrogen produced = ?
Mass of excess reactant left = ?
Solution:
Chemical equation:
Mg + 2HCl → MgCl₂ + H₂
Number of moles of Mg:
Number of moles = mass/molar mass
Number of moles = 50 g/ 24 g/mol
Number of moles = 2.1 mol
Number of moles of HCl:
Number of moles = mass/molar mass
Number of moles = 75 g/ 36.5 g/mol
Number of moles = 2.1 mol
now we will compare the moles of hydrogen gas with both reactant.
Mg : H₂
1 : 1
2.1 : 2.1
HCl : H₂
2 : 1
2.1 : 1/2×2.1 = 1.05 mol
HCl is limiting reactant and will limit the yield of hydrogen gas.
Mass of hydrogen:
Mass = number of moles × molar mass
Mass= 1.05 mol ×2 g/mol
Mass = 2.1 g
Mg is present in excess.
Mass of Mg left:
HCl : Mg
2 : 1
2.1 : 1/2×2.1 = 1.05
Out of 2.1 moles of Mg 1.05 react with HCl.
Moles of Mg left = 2.1 mol - 1.05 mol = 1.05 mol
Mass of Mg left:
Mass = number of moles × molar mass
Mass = 1.05 mol × 24 g/mol
Mass = 25.2 g
