Answer: 2. Bonds and bond energies of the molecule
Explanation:
The absorption spectrum is an electromagnetic spectrum which is used for observing the intensity of the radiations which have been absorbed by the substances shown by the pattern of dark lines or bands. Infrared and microwave spectroscopy are specialized techniques which are used for observing the bonds and bond energy of the molecules which can be observed by measuring the frequencies at which the radiations are absorbed.
Answer:
The correct answer is - B. dissolving → evaporation filtration → crystallisation
Explanation:
The method of the preparation of a pure sample of copper(II) sulfate from dilute sulfuric acid and copper II oxide is given as follows:
step 1. Adding dilute sulfuric acid into a beaker. Using bunsen burner heat the beaker.
step 2. Adding the copper (II) oxide into the beaker and give it a little time at a time to the warm dilute sulfuric acid and stir
step 3. Filtering the mixture into an evaporating vessel to remove the excess copper (II) oxide and water from the filtrate.
Step 4. leave the rest filtrate to crystallize.
Copper (II) Oxide {CuO (s)} + Dilute Sulfuric Acid {H2SO4 (aq)} → Copper (II) Sulphate {CuSO4 (s)} + Water {H2O}
New, stronger bacteria have evolved that are resistant to antibiotics.
Answer:
C₃H₉N
Explanation:
The empirical formula of a compound is the fundamental and basic possible formula that shows the mole ratio of the atoms of each element in a molecule of the compound.
mole ratio of carbon = 60.94/12 = 5.078
mole ratio of hydrogen = 15.36/1 = 15.36
mole ratio of nitrogen = 23.70/14 = 1.693
Now; we will divide by the smallest value
So; carbon = 5.078/1.693 = 2.99 ≅ 3.0
hydrogen = 15.36/1.693 = 9.07 ≅ 9.0
nitrogen = 1.693/1.693 = 1 ≅ 1
Thus, the empirical formula is = C₃H₉N
