Measuring the ratio of C-14 to C-12 in the remains of dead organisms to determine how much time has passed since the organism died
the answer is D
Answer:
Option D. 30 mL.
Explanation:
Step 1:
The balanced equation for the reaction. This is given below:
HNO3 + KOH —> KNO3 + H2O
From the balanced equation above,
The mole ratio of the acid, nA = 1
The mole ratio of the base, nB = 1
Step 2:
Data obtained from the question. This include the following:
Volume of base, KOH (Vb) =.?
Molarity of base, KOH (Mb) = 0.5M
Volume of acid, HNO3 (Va) = 10mL
Molarity of acid, HNO3 (Ma) = 1.5M
Step 3:
Determination of the volume of the base, KOH needed for the reaction. This can be obtained as follow:
MaVa / MbVb = nA/nB
1.5 x 10 / 0.5 x Vb = 1
Cross multiply
0.5 x Vb = 1.5 x 10
Divide both side by 0.5
Vb = (1.5 x 10) /0.5
Vb = 30mL
Therefore, the volume of the base, KOH needed for the reaction is 30mL.
Mostly and for what I would say is A
Answer:
B.0.2 J/g°C
Explanation:
From the attached picture;
- Heat attained in the solid phase is 200 Joules
- Change in temperature is 50°C ( from 0°C to 50°C)
- Mass of the solid is 20 g
We are required to determine the specific heat capacity of the substance;
- We need to know that Quantity of heat is given by the product of mass,specific heat capacity and change in temperature.
- That is; Q = mcΔT
Rearranging the formula;
c = Q ÷ mΔT
Therefore;
Specific heat = 200 J ÷ (20 g × 50°c)
= 0.2 J/g°C
Thus, the specific heat of the solid is 0.2 J/g°C
