Easy it’s 86 so the third option
Answer:
Mass = 20 g
Explanation:
Given data:
Number of moles of He = 5 mol
Mass of He = ?
Solution:
Formula:
Number of moles = mass/ molar mass
Molar mass = 4 g/mol
by putting values,
5 mol = Mass / 4 g/mol
Mass = 5 mol × 4 g/mol
Mass = 20 g
Answer:
1.8 × 10⁻⁴ mol M/s
Explanation:
Step 1: Write the balanced reaction
2 Br⁻ ⇒ Br₂
Step 2: Establish the appropriate molar ratio
The molar ratio of Br⁻ to Br₂ is 2:1.
Step 3: Calculate the rate of appearance of Br₂
The rate of disappearance of Br⁻ at some moment in time was determined to be 3.5 × 10⁻⁴ M/s. The rate of appearance of Br₂ is:
3.5 × 10⁻⁴ mol Br⁻/L.s × (1 mol Br₂/2 mol Br⁻) = 1.8 × 10⁻⁴ mol Br₂/L.s
What's wrong with this setup is the substrate on which you have positioned
the drop is "dirty and unclean" meaning it is not being dampened by
the solution. This action can be corrected by comprehensively cleaning the
substrate where the drop will be positioned.
