To convert Celsius to kelvin, we need to know the formula. Kelvin = Celsius + 273.15. Now, we can figure out how many degrees kelvin -12 degrees Celsius is.
Kelvin = -12 + 273.15
Kelvin = 261.15
The (B) answer (B) is (B) (B) (B)
<span>The reason it will be 7 for some titrations is that when you titrates a strong acid with a strong base for example HCl and NaOH the salt formed is conjugate base of strong acid and will be a very weak base
That means that it cannot produce any OH^-1 and all the H+ has been converted to water.The only source of H+ or OH is water with a Ka of 10^-14 so the pH = -log [H+]=-log 10^-7 = 7
second reason is
When you titrates a weak acid with strong base at equivalence point
only a water solution of the conjugate base exists
CH3COOH + NaOH ----- Na+ CH3COO^-1 + H2O
Since the conjugate base is the conjugate base of a weak acid it will hydrolyze in water like so
for instance Na+ CH3COO^-1 + HCl---- CH3COOH + NaCl the equivalence point will be way BELOW 7 and in the case of above will be less than 5. So pH of 7 at equivalence point is only reached in strong acid strong base titrations.
hope this helps</span>
Answer:
5: 0.16
6: 50
Explanation:
Question 5:
We can use the equation density = mass/ volume.
We already have the mass (12g), but now we need to find the volume of the cylinder.
The equation for this is πr²h
So we know the radius is 2 and the height is 6.
π x (2)² x 6 = 24π = 75.398cm³
Now we can use the density equation above:
12/75.398 = 0.1592g/cm³ = 0.16g/cm³.
Question 6:
This time, we have to rearrange the equation density = mass/ volume to find the mass.
We know mass = density x volume.
From the question, the density is 2.5g/mL and the volume is 20mL.
Following the equation above, we do 2.5 x 20 to get 50g.