Answer:
pH = 8.25
Explanation:
The acidity or basicity of a solution is measured by its pH. The pH scale ranges from 0 to 14. Solutions having pH from 0-6.9 are considered acidic, at 7 neutral and basic when ranging from 7.1-14.
pH is calculated as,
pH = - log [H⁺] ---- (1)
Where;
[H⁺] = concentration of Acid
Also, for bases pH i calculated using following formula,
pH = 14 - pOH
Therefore, Putting value of H⁺ in equation 1,
pH = - log [5.6 × 10⁻⁹]
pH = 8.25
The solution provided is basic in nature.
Answer:
0.4 M
Explanation:
Molarity is defined as moles of solute, which in your case is sodium hydroxide,
NaOH
, divided by liters of solution.
molarity
=
moles of solute
liters of solution
Notice that the problem provides you with the volume of the solution, but that the volume is expressed in milliliters,
mL
.
Moreover, you don't have the number of moles of sodium hydroxide, you just have the mass in grams. So, your strategy here will be to
determine how many moles of sodium hydroxide you have in that many grams
convert the volume of the solution from milliliters to liters
So, to get the number of moles of solute, use sodium hydroxide's molar mass, which tells you what the mass of one mole of sodium hydroxide is.
7
g
⋅
1 mole NaOH
40.0
g
=
0.175 moles NaOH
The volume of the solution in liters will be
500
mL
⋅
1 L
1000
mL
=
0.5 L
Therefore, the molarity of the solution will be
c
=
n
V
c
=
0.175 moles
0.5 L
=
0.35 M
Rounded to one sig fig, the answer will be
c
=
0.4 M
Explanation:
Answer:
The correct answer is - D. Freezing point depression.
Explanation:
When rock salt is spread over snow-covered icy roads, it generates a liquid layer over it by melting from the surface thereby lowering or depression in the freezing point below the ice.
Therefore, due to this liquid layer comes into the contact with the ice present on the road and causes other ice to melts. This keeps on decreasing the volume of the ice on the road therefore, rock salts spread on the roads during a snowstorm.
Answer:
Enzyme
Explanation:
An enzyme is an organic catalyst that speeds up a reaction but can be recovered unchanged.
Human lactase consists of 4092 amino acid groups and has a molar mass of about 280 000 u, so it has a complex structure.
Advantages of using tidal energy:
-Environment-friendly
-A highly predictable energy source
-High energy density
-Operational and maintenance costs are low
-An inexhaustible source of energy
Disadvantages of using tidal energy:
-High tidal power plant construction costs.
-Negative influence on marine life forms.
-Location limits.
-The variable intensity of sea waves.