Calculate the volume in L of 12.9 g of NO2 at STP. 46.0 L NO2
12.9 L NO2
26.5 L NO2
6.28 L NO2

6.28 L

Explanation:

Given data:

Volume of NO₂ = ?

Mass of NO₂ = 12.9 g

Temperature and pressure = ?

Solution:

First of all we will calculate the number of moles of gas.

Number of moles = mass/molar mass

Number of moles = 12.9 g/ 46 g/mol

Number of moles = 0.28 mol

At standard temperature and pressure 1 mole of gas occupy 22.4 L volume.

Thus,

0.28 mol × 22.4 L/1 mol

6.27 L ≅ 6.28 L

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.