1. ₉¹⁹F
2. Mg(OH)₂
3. 2H₂ + O₂ ⇒ 2H₂O
<h3>Further explanation</h3>
1. Fluorine, atomic number : 9 , mass number = 19
Symbol : ₉¹⁹F
protons=electrons=atomic number = 9
neutrons = mass number - atomic mass
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Configuration : [He] 2s² 2p⁵
2. Magnesium hydroxide is an ionic compound and is a strong base consisting of 2 ions:
Positive ion: Magnesium: Mg²⁺
negative ion: Hydroxide: OH⁻
The charges of the two are crossed, so that the compound becomes:
Mg(OH)₂
3. Reaction :
H₂ + O₂ --------> H₂O
give coefficient :
aH₂ + bO₂ --------> H₂O
H, left = 2a, right 2⇒2a=2⇒a=1
O, left = 2b, right 1⇒2b=1⇒b=0.5
Reaction becomes :
H₂ + 0.5O₂ --------> H₂O x 2
2H₂ + O₂ --------> 2H₂O
Given
Mass of NO - 824 g
Molar mass of NO - 30.01g/mol
No of moles of NO = Given mass/Molar mass
No of moles of NO = 824/30.01= 27.45 mole
Hence 27.5 moles of NO are formed!
3 carbons and 8<span> hydrogens = </span>11 atoms<span> in propane </span>per molecule
<span>2.12 mol C3H8
</span>6.02<span> x </span>1023<span> molecules of C3H8
</span>
11 atoms
Moles of H⁺ released by each mole of acid = 3
Moles of H⁺ released = 3
Moles of OH⁻ released = 1.75
Moles of H⁺ remaining = 3 - 1.75 = 1.25 mol/dm³
pH = -log[H⁺]
pH = -log(1.25)
pH = -0.1
Answer:
oxygen is limiting reactant
Explanation:
Given data:
Mass of phosphorus = 25.0 g
Mass of oxygen = 50.0 g
What is limiting reactant ?
Solution:
Chemical equation:
P₄ + 5O₂ → P₄O₁₀
Number of moles of P₄:
Number of moles = mass/molar mass
Number of moles = 25.0 g/ 123.89 g/mol
Number of moles = 0.20 mol
Number of moles of O₂:
Number of moles = mass/molar mass
Number of moles = 50.0 g/ 32 g/mol
Number of moles = 1.56 mol
now we will compare the moles of reactants with product:
P₄ : P₄O₁₀
1 : 1
0.20 : 0.20
O₂ : P₄O₁₀
5 : 1
1.56 : 1/5×1.56 = 0.312 mol
Less number of moles of product are formed by the oxygen thus it will act as limiting reactant.