1 kg ----------- 2.20462 pounds
1.8 kg -------- ??
1.8 x 2.20462 / 1 => 3.96832 pounds
1.)Boron
2.)Cadmium has 48 electrons not 121 Mercury has 80 And Copernicum so they all have no 121 electrons
3.)Hydrogen
Answer:
15. 2.66 moles .
16. 2.09L.
Explanation:
Molarity of a solution is simply defined as the mole of solute per unit litre of the solvent. Mathematically, it is represented as:
Molarity = mole /Volume.
With the above formula, let us answer the questions given above
15. Data obtained from the question include the following:
Volume of solution = 1.4L
Molarity = 1.9M
Mole of solute =.?
Molarity = mole /Volume
1.9 = mole / 1.4
Cross multiply
Mole = 1.9 x 1.4
Mole = 2.66 moles
Therefore, the mole of the solute present in the solution is 2.66 moles.
16. Data obtained from the question include the following:
Mole of solute = 0.46 mole
Molarity = 0.22M
Volume of solvent (water) =.?
Molarity = mole /Volume
0.22 = 0.46/Volume
Cross multiply
0.22 x Volume = 0.46
Divide both side 0.22
Volume = 0.46/0.22
Volume = 2.09L
Therefore, 2.09L of water is required.
The empirical and molecular formulas will be 
and 
respectively.
<h3>Empirical and molecular formula</h3>
The compound contains C, H, and O.
C = 61.15/12 = 5.0958
H = 5.3/1 = 5.3
O = 31.55/16 = 1.9719
Divide by the smallest
C = 2.6
H = 2.7
O = 1
Thus, the empirical formula is
Empirical formula mass = (12x5) + (1x5) + 16x2 = 97
n = 152.15/97 = 2
The molecular formula is
More on molecular and empirical formulas can be found here: brainly.com/question/14425592
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Different isotopes of the same element must have a different mass number
