Explanation:
reaction A is exothermic reaction as a substance is produced from two substances
and
reaction B is endothermic as two substances are formed from one complex structure
Certain naturally occurring radioactive isotopes are unstable: Their nucleus breaks apart, undergoing nuclear decay. ... All elements with 84 or more protons are unstable; they eventually undergo decay. Other isotopes with fewer protons in their nucleus are also radioactive.
Answer:
8.90
Explanation:
Density = mass ÷ volume
D = 222.50 g ÷ 25.00
= 8.9
The density of the unknown metal is 8.90.
Hope that helps.
Answer:
6.178 g.
Explanation:
- KCl is ionized in the solution as:
<em>KCl → K⁺ + Cl⁻.</em>
<em></em>
∴ [KCl] = [K⁺] = [Cl⁻] = 0.193 M.
<em>Molarity is defined as the no. of moles of the solute per 1.0 L of the solution.</em>
<em />
∵ M = [(mass/molar mass)KCl][(1000)/(V of the solution)].
<em>∴ mass of KCl = (M)(molar mass of KCl)(V of the solution)/1000</em> = (0.193 M)(74.55 g/mol)(430.0 mL)/1000 = <em>6.178 g.</em>
<em></em>
Th actual yield of the reaction is 24.86 g
We'll begin by calculating the theoretical yield of the reaction.
2Na + Cl₂ → 2NaCl
Molar mass of Na = 23 g/mol
Mass of Na from the balanced equation = 2 × 23 = 46 g
Molar mass of NaCl = 23 + 35.5 = 58.5 g/mol
Mass of NaCl from the balanced = 2 × 58.5 = 117 g
From the balanced equation above,
46 g of Na reacted to produce 117 g of NaCl.
Therefore,
11.5 g of Na will react to produce = (11.5 × 117) / 46 = 29.25 g of NaCl.
Thus, the theoretical yield of NaCl is 29.25 g.
Finally, we shall determine the actual yield of NaCl.
- Theoretical yield = 29.25 g
Actual yield = Percent yield × Theoretical yield
Actual yield = 85% × 29.25
Actual yield = 0.85 × 29.25 g
Actual yield = 24.86 g
Learn more about stoichiometry: brainly.com/question/25899385
