The reaction produces 2.93 g H₂.
M_r: 133.34 2.016
2Al + 6HCl → 2AlCl₃ + 3H₂
<em>Moles of AlCl₃</em> = 129 g AlCl₃ × (1 mol AlCl₃/133.34 g AlCl₃) = 0.9675 mol AlCl₃
<em>Moles of H₂</em> = 0.9675 mol AlCl₃ × (3 mol H₂/2 mol AlCl₃) = 1.451 mol H₂
<em>Mass of H₂</em> = 1.451 mol H₂ × (2.016 g H₂/1 mol H₂) = 2.93 g H₂
The atomic number is based on the number of protons, so the atomic number would be 43
Answer:
P = 58.52 atm
Explanation:
Given data:
Mass of sample = 32.0 g
Pressure of sample = ?
Volume of gas = 850 cm³
Temperature of gas = 30°C
Solution:
Number of moles of gas:
Number of moles = mass/molar mass
Number of moles = 32.0 g/ 16 g/mol
Number of moles = 2 mol
Pressure of gas:
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
Now we will convert the temperature.
30+273 = 303 K
850 cm³ × 1L /1000 cm³ = 0.85 L
by putting values,
P× 0.85 L = 2 mol × 0.0821 atm.L/ mol.K × 303 K
P = 49.75 atm.L/ 0.85 L
P = 58.52 atm
Answer:
[tex]2KCl + Zn {}^{2 + } → 2K {}^{ + } + ZnCl _{2} \\ molecular \: mass \: of \: zinc \: chloride = 65 + (35.5 \times 2) = 136 \: g \\ molecular \: mass \: of \: potassium \: chloride = 39 + 35.5 = 74.5 \: g
Answer:
Rubidium (Rb).
Explanation:
From the question given above, the following data were obtained:
Electronic configuration => 1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s¹
Name of element =?
To know the name of the element with the above electronic configuration, we shall determine the atomic number of the element. This can be obtained as follow:
Number of electrons = 2 + 2 + 6 + 2 + 6 + 2 + 10 + 6 + 1
Number of electrons = 37
Next, we shall determine the number of protons. This can be obtained as follow:
From the question given above, the element has no charge. Hence the element contains equal numbers of protons and electrons.
Number of electrons = 37
Number of protons = number of electrons = 37
Next, we shall determine the atomic number. This can be obtained as follow:
The atomic number of an element is simply defined as the number of protons present in the atom of the element. Thus,
Atomic number = proton number
Proton is = 37
Therefore,
Atomic number = 37
Finally, we shall determine the name of the element by comparing the atomic number of those in the periodic table.
Thus, the element with the above electronic configuration is Rubidium (Rb) since no two elements have the same atomic number
