The mass of potassium hydroxide required to make 300.ocm3 of 0.4 moldm-3 solution is {KOH = 56.0}
26.88g
13.44g
6.72g
3.36g
Correct answer is C
300cm3 of 0.4moldm3
1000cm3 contains 0.4mole
300cm3 will contain \(\frac{300 \times 0.4}{1000}\)
= 0.12mole
Number of moles = \(\frac{Mass}{\text {Molecular mass}}\)
Mass = number of moles x m.mass
= 0.12 x 56 = 6.72g
Chemicals that are produced in small quantities and with very degree of purity are
Bulk chemicals
Fine chemicals
Heavy chemicals
Light chemicals
Correct answer is B
No explanation has been provided for this answer.
The boiling points of HF, H2O and NH3 increase in the order of
NH3
H2O < HF
HF < NH3 < H2O
NH3 < HF < H2O
Correct answer is D
Ammonia = -33.34°C; Hydrogen fluoride = 19.5°C; Water = 100°C
10:10:10
20:10:10
10:10:20
20:20:10
Correct answer is B
For the cultivation of yam and cassava, the recommended NPK fertilizer ratio is 20:10:10. This means the fertilizer contains a higher percentage of nitrogen (N) compared to phosphorus (P) and potassium (K). Nitrogen is essential for promoting vegetative growth and leaf development, which is important for yam and cassava during their early stages of growth.
Assuming a sow was serviced on May 1 and conceived the same day, the expected date of parturition is
June 2
September 30
August 24
October 2
Correct answer is B
The gestation period for a sow (female pig) is approximately 3 months, 3 weeks, and 3 days, which is equivalent to about 114 days.
If the sow was serviced (mated) on May 1, we can calculate the expected date of parturition (giving birth) as follows:
Count 3 months from May 1: May + 3 months = August 1
Count 3 weeks from August 1: August 1 + 3 weeks = August 22
Count 3 more days from August 22: August 22 + 3 days = August 25
So, based on the gestation period, the expected date of parturition is around August 25. However, since not all months have the same number of days, we need to adjust for the extra days to reach the actual parturition date.
Counting from August 25 to September 30, there are 36 days (25 days in August and 5 days in September). Adding these 36 days to August 25:
August 25 + 36 days = September 30
Therefore, the expected date of parturition is September 30.