<em>Answer: </em>D
<em>Explanation:</em>
chemical formula of methane: CH4
electron configuration of C: 2,4
electron configuration of H: 1
there are 4 hydrogen atoms that donated 1 electron each to C
therefore it's D.
Answer:
B.) If sodium carbonate is added to vinegar, the reaction will absorb heat.
Explanation:
A.) is incorrect because this is not testable. Rather, it is just an opinion that cannot be proven correct or incorrect.
B.) is correct because this statement is testable. Tests need to be run to determine the accuracy of the statement.
C.) is incorrect because this statement explains something that does not need to be tested. It is an example of a physical change when one tears a piece of paper.
D.) is incorrect because this is already a true statement. It is obvious that not all reactions absorb/release heat. While tests could be run to further prove this statement true, it is already considered accurate.
Answer: C= 0.406 M
Explanation:
Solution.
ν
=
0.730
m
o
l
;
ν=0.730mol;
V
=
1.8
⋅
1
0
3
m
L
=
1.8
L
;
V=1.8⋅10
3 mL=1.8L;
C=0.730mol
1.8 L=0.406 M
C= 1.8L
0.730mol =0.406M
The student made a mistake because he did not convert a unit of volume from milliliters to liters. After all, molarity is defined as the number of moles of solute per liter of solution.
Answer: 0.100 m 
Explanation:
Elevation in boiling point is given by:

= Elevation in boiling point
i= vant hoff factor
= boiling point constant
m= molality
1. For 0.100 m 
, i= 3 as it is a electrolyte and dissociate to give 3 ions. and concentration of ions will be 
2. For 0.100 m 
, i= 2 as it is a electrolyte and dissociate to give 2 ions, concentration of ions will be 
3. For 0.200 m 
, i= 1 as it is a non electrolyte and does not dissociate, concentration of ions will be 
4. For 0.060 m 
, i= 4 as it is a electrolyte and dissociate to give 4 ions. and concentration of ions will be 
Thus as concentration of solute is highest for
, the elevation in boiling point is highest and thus has the highest boiling point.
Answer:
C) 3.3 x 104 grams
Explanation:
1 mole of water contains 6.02 × 10^23 atoms
1.1 × 10^27 atoms will contain;
1.1 × 10^27 ÷ 6.02 × 10^23
= 0.1827 × 10^( 27 - 23)
= 0.1827 × 10^(4)
= 1.827 × 10³ moles of water.
To convert mole to mass in grams, we use the formula;
mole (n) = mass (m) ÷ molar mass (MM)
Molar mas of water (H2O) = 1(2) of H + 16 of O = 18g/mol
mole = mass/molar mass
1.827 × 10³ = mass / 18
mass = 1.827 × 10³ × 18
mass = 32.886 × 10³
mass = 3.286 × 10⁴
mass = 3.3 × 10⁴ grams