Answer:
number of Calcium on the periodic table is 20
Answer: " <span>1.8 * 10²⁴ molecules of O₂ " .
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3.0 moles O₂ * (6.02 * 10²³ molecules O₂ / 1 mol O₂) =
[ (3.0) *(6.02 * 10²³) ] molecules O₂
= 1.806 * 10²⁴ ; round to 2 significant figures.
= 1.8 * 10²⁴ molecules of O₂ .
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Answer:
Mass = 76.176 g
Explanation:
Given data:
Mass of lead(II) chloride produced = 62.9 g
Mass of lead(II) nitrate used = ?
Solution:
Chemical equation:
Pb(NO₃)₂ + 2HCl → PbCl₂ + 2HNO₃
Number of moles of lead(II) chloride:
Number of moles = mass/molar mass
Number of moles = 62.9 g/ 278.1 g/mol
Number of moles = 0.23 mol
Now we will compare the moles of lead(II) chloride with Pb(NO₃)₂ from balance chemical equation:
PbCl₂ : Pb(NO₃)₂
1 : 1
0.23 : 0.23
Mass of Pb(NO₃)₂:
Mass = number of moles × molar mass
Mass = 0.23 mol × 331.2 g/mol
Mass = 76.176 g
Answer:
This question appear incomplete
Explanation:
This question appear incomplete because an equation to show the production of sodium chloride from calcium chloride should have been illustrated. However, if the balanced chemical equation showing sodium chloride (NaCl) been a product of a reaction involving calcium chloride (CaCl₂) as a reactant (shown below) is to be used, then we start by writing a complete balanced chemical equation
CaCl₂ + Na₂CO₃ ⇒ CaCO₃ + 2NaCl
From the equation above, it can be deduced that 1 mole of CaCl₂ is required to produce 2 moles of NaCl, thus how many moles of CaCl₂ will be required to produce 6.5 moles of NaCl.
1 mole of CaCl₂ = 2 moles of NaCl
? moles of CaCl₂ = 6.5 moles of NaCl
cross multiply
? moles of CaCl₂ = 6.5 × 1/2
? moles of CaCl₂ = 3.25 moles of CaCl₂
3.25 moles of CaCl₂ will be needed to produce 6.5 moles of NaCl
Answer:
The mass (M) and speed of an object (v)
Explanation: