Air is a mixture because it is made up of many constituents like oxygen, argon etc. it can be physically separated by fractional distillation. it doesnt have a formula unlike compounds and elements. its composition varies differently with its constituents.
Answer:
Lithium only has one pair of unpaired electrons.
Explanation:
Answer : The correct option is, transverse wave.
Explanation :
Longitudinal waves : It is defined as the waves in which the particles of the medium move in the direction of the wave.
Transverse wave : It is defined as the waves in which the particles of the medium travel perpendicularly to the direction of the wave.
Surface wave : It is defined as a combination of transverse and longitudinal waves.
From the given image we conclude that, this illustration depict the transverse wave because the particles of the medium move perpendicularly to the direction of the wave.
Hence, the type of wave is, transverse wave
The given question is incomplete. The complete question is:
A chemist prepares a solution of barium chloride by measuring out 110 g of barium chloride into a 440 ml volumetric flask and filling the flask to the mark with water. Calculate the concentration in mole per liter of the chemist's barium chloride solution. Round your answer to 3 significant digits.
Answer: Concentration of the chemist's barium chloride solution is 1.20 mol/L
Explanation:
Molarity of a solution is defined as the number of moles of solute dissolved per liter of the solution.

where,
n = moles of solute
= volume of solution in L
moles of
(solute) = 
Now put all the given values in the formula of molality, we get

Therefore, the molarity of solution is 1.20 mol/L
Answer:
The answer to your question is 0.269 g of Pb
Explanation:
Data
Lead solution = 0.000013 M
Volume = 100 L
mass = 0.269 g
atomic mass Pb = 207.2 g
Chemical reaction
2Pb(s) + O₂(aq) + 4H⁺(aq) → 2H₂O(l) + 2Pb₂⁺(aq)
Process
1.- Calculate the mass of Pb in solution
Formula
Molarity = 
Solve for number of moles
Number of moles = Volume x Molarity
Substitution
Number of moles = 100 x 0.000013
Number of moles = 0.0013
2.- Calculate the mass of Pb formed.
207.2 g of Pb ----------------- 1 mol
x g ----------------- 0.0013 moles
x = (0.0013 x 207.2) / 1
x = 0.269 g of Pb