
Which of the following is a period 4 representative element?
O A. C
O B. An
O C. Ti
O D. K



- Carbon (from Latin: carbo "coal") is a chemical element with the symbol C and atomic number 6. It is nonmetallic and tetravalen - making four electrons available to form covalent chemical bonds. It belongs to group 14 of the periodic table. Carbon makes up only about 0.025 percent of Earth's crust.
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<h3>→XxKim02xX</h3>
Answer:
Mass of hydrogen gas produced = 0.2 g
Explanation:
Given data:
Number of moles of Mg = 0.2 mol
Number of moles of HCl = 0.2 mol
Mass of hydrogen gas produced = ?
Solution:
Chemical equation:
Mg + 2HCl → MgCl₂ + H₂
Now we will compare the moles of of hydrogen with Mg and HCl.
Mg : H₂
1 : 1
0.2 : 0.2
HCl : H₂
2 : 1
0.2 : 1/2×0.2 = 0.1
HCl produced less number of moles of hydrogen gas it will act as limiting reactant.
Mass of hydrogen:
Mass = number of moles × molar mass
Mass = 0.1 mol × 2 g/mol
Mass = 0.2 g
Answer:
a, d, f
Explanation:
ΔHrxn = ΔH(CCl4) -ΔH(CH4) = - 106.7 -(-74.8) = - 31.9 kJ/mol