<span>The state of the helium in its natural form is gaseous and is a chemical element of colorless aspect and belongs to the group of noble gases. The atomic number of helium is 2. The chemical symbol of helium is He. For the following we focus on those elements and relate it with similar chemical properties. Then we find that; Neon, Hydrogen, Boron and Carbon are related to helium, either by proximity in their atomic number or period or by their group.</span>
1. Synthesis or Combination reaction
2. Double replacement reaction
3. Single Replacement reaction
4. Decomposition reaction
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Answer:
H₂ is excess reactant and O₂ the limiting reactant
Explanation:
Based on the chemical reaction:
2H₂(g) + O₂(g) → 2H₂O
<em>2 moles of H₂ react per mole of O₂</em>
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To find limiting reactant we need to convert the mass of each reactant to moles:
<em>Moles H₂ -Molar mass: 2.016g/mol-:</em>
10g H₂ * (1mol / 2.016g) = 4.96 moles
<em>Moles O₂ -Molar mass: 32g/mol-:</em>
22g O₂ * (1mol / 32g) = 0.69 moles
For a complete reaction of 0.69 moles of O₂ are needed:
0.69mol O₂ * (2mol H₂ / 1mol O₂) = 1.38 moles of H₂
As there are 4.96 moles,
<h3>H₂ is excess reactant and O₂ the limiting reactant</h3>
Answer:
See below.
Step-by-step explanation:
The two isotopes are Cl-35 and Cl-37.
The average atomic mass (35.45 u) is closer to 35 u, so most of the atoms are Cl-35.
mass number = number of protons + number of neutrons
A = p + n
35 = 17 + n
n = 35 – 17
n = 18
∴ Most chlorine atoms contain 18 neutrons.
