Answer:
1.13 M
Explanation:
Given data
- Mass of luminol (solute): 15.0 g
- Volume of solution = volume of water = 75.0 mL = 0.0750 L
- Molar mass of luminol: 177.16 g/mol
The molarity of the stock solution of luminol is:
M = mass of solute / molar mass of solute × liters of solution
M = 15.0 g / 177.16 g/mol × 0.0750 L
M = 1.13 M
Iron accounts for about 86% of the Earth's core and Silicon is next at only 6%. Iron is by far the most abundant element in the Earth's core.
Answer:
30.0g/mol
Explanation:
Step 1: Given data
- Pressure (P): 1 atm (standard pressure)
- Temperature (T): 273.15 K (standard temperature)
Step 2: Calculate the moles of the gas
We will use the ideal gas equation.
Step 3: Calculate the molar mass of the gas
4.16 × 10⁻³ moles correspond to a mass of 0.125 g. The molar mass of the gas is:
Answer:
elment ? atómic 71⁰349⁹⁰291
B. The cathode is the electrode where the reduction takes place took test