Answer: Isotopes of an atom are different because they have different atomic masses and different number of neutrons within their nucleus. They are the same since they will always have the same atomic number/number of protons in their nucleus.
Explanation:
The mass of 6.12 moles of arsenic (As) is calculated to be approximately 459g.
HOW TO CALCULATE MASS:
The mass of a substance can be calculated by multiplying the number of moles of a substance by its molar mass. That is;
Mass of Arsenic = no. of moles of As × molar mass of As.
According to this question, 6.12 moles of arsenic was given and its molar mass is 74.92g/mol.
Mass of As = 6.12 mol × 74.92g/mol
Mass of As = 459g
Therefore, the mass of 6.12 moles of arsenic (As) is calculated to be approximately 459g.
Learn more about mass calculations at: brainly.com/question/8101390
Answer:
+15.8°
Explanation:
The formula for the observed rotation (α) of an optically active sample is
α = [α]<em>lc
</em>
where
<em>l</em> = the cell path length in decimetres
<em>c</em> = the concentration in units of g/100 mL
[α] = the specific rotation in degrees
1. Convert the concentration to units of g/100 mL
2. Calculate the observed rotation
Answer:
0.486 L
Explanation:
Step 1: Write the balanced reaction
2 KCIO₃(s) ⇒ 2 KCI (s) + 3 O₂(g)
Step 2: Calculate the moles corresponding to 1.52 g of KCIO₃
The molar mass of KCIO₃ is 122.55 g/mol.
1.52 g × 1 mol/122.55 g = 0.0124 mol
Step 3: Calculate the moles of O₂ produced from 0.0124 moles of KCIO₃
The molar ratio of KCIO₃ to O₂ is 2:3. The moles of O₂ produced are 3/2 × 0.0124 mol = 0.0186 mol
Step 4: Calculate the volume corresponding to 0.0186 moles of O₂
0.0186 moles of O₂ are at 37 °C (310 K) and 0.974 atm. We can calculate the volume of oxygen using the ideal gas equation.
P × V = n × R × T
V = n × R × T/P
V = 0.0186 mol × (0.0821 atm.L/mol.K) × 310 K/0.974 atm = 0.486 L
<span>C. In order for a nonmetal to obey the octet rule, it gains electrons.</span>
