Answer:
a. because it is an element
Explanation:
its pure because it only has one type of atom, making it an element
<u>Answer:</u>
<em>4.5 L water we have in litres (L).</em>
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<u>Explanation:</u>

where
= Final T - Initial T
Q is the heat energy in calories
c is the specific heat capacity (for water 1.0 cal/(g℃))
m is the mass of water
Plugging in the values

So,
Volume of water = mass/density

=4.5 L (Answer)
Answer:
O B. Convert the 10 g of NaCl to moles of NaCl.
Explanation:
The formula for finding the molality is m=moles of solute/kg of solvent. The solute for this question is NaCl and the solvent is water.
(10g NaCl)(1 mol NaCl/58.44g NaCl)=0.1711 mol NaCl
58.44 is the molar mass of NaCl
m=0.1711 mol NaCl/2 kg H2O
m=0.085557837
Since the given solubility is 350 ppm, convert it first with fraction of solubility. by dividing the solubility with 10^6
S = 350 / 10^6
s = 3.5 x 10^-4
the multiply it to the total solution to calculate the amount of substance present
m = ( 3.5 x 10^-4 ) ( 1.01 )
m = 3.535 x 10^-4 g of the substance present