79 and a charge of -2 thx for the points
manganese The metal that is used as a sacrificial electrode to prevent the rusting of iron is manganese.
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}
Answer:
B. Decreasing the pressure applied to the gas molecules
Explanation:
According to Boyle's Law, the pressure of the gas is inversely proportional to the volume of the gas. So, the option B is correctly implied to it.
Other values such as Temperature, Number of molecules are inversely proportional to the volume of the gas.
Size of the gas molecules is negligible as compared to volume.
The answer is Al.
If it is a main group element with 3 electrons in its Lewis dot structure, it must be in group 3A. If it is in the 3p orbital section, then it must be in period 3, since the p orbital is a valence orbital and the number that preceeds it is the principal quantum number. Therefore, your answer is the element in period 3 and group 3A, which is aluminum.
