Answer:
(c) The retention time would be higher (d) The retention time would be lower.
Explanation:
For the polar solutes which were separated using the hydrophilic interaction chromatography (HILIC) with a strongly polar bonded phase, the retention time would be higher if eluent were changed from 80 vol% to 90 vol% acetonitrile in water.
However, for the polar solutes which were separated using the normal-phase chromatography on bare silica with methyl t=butyl ether and 2-propanol solvent, the retention time would be lower if the eluent were changed from 40 vol% to 60 vol% 2-propanol.
Answer: 1.25 miles per minute
Explanation:
Average speed is the rate of change of total distance covered per unit time.
i.e Average speed = (Total distance / Time taken)
Total distance covered = (25miles + 40 miles + 70 miles + 15 miles)
= 150 miles
Total time taken = ( 15 minutes + 30 minutes + 1 hour + 15 minutes) = 120 minutes
Since 60 minutes = 1 hour, the total time taken is 120 minutes
Now, apply Average speed = (Total distance / Time taken)
= (150 miles / 120 minutes)
= 1.25 miles per minutes
Thus, Joseph drove with an average speed of 1.25 miles per minute.
1.matter is made up of small particles
2.particles of matter are in constant random motion
Explanation:
1.Particles eg of salt can be crashed into smaller particles 2.When you sprinkle pollen grains on water in a beaker and observe using a hand lens U'll see they are moving randomly
×
atoms are in 0.0015 mol of fluorine gas
<h3>
What is fluorine?</h3>
The chemical element fluorine has an atomic number of 9 and the symbol F. The lightest halogen, it is an extremely poisonous, pale yellow diatomic gas under normal conditions. With the exception of argon, neon, and helium, it reacts with every other element, making it the most electronegative and reactive element.
Fluorine is the 24th most abundant element overall and the 13th most abundant on Earth. When added to metal ores to decrease their melting temperatures for smelting, fluorite, the main mineral source of fluorine that gave the element its name, was first recorded in 1529. The Latin word fluo, which means "flow," gave the mineral its name.
Learn more about fluorine
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