Đề Khảo Sát Chất Lượng HSG Môn KHTN

What is the carbon content in the alloy called steel?

• From 2% to 6%

• Below 2%

• From 2% to 5%

• Above 6%

Which pair of substances does not react?

• ZnSO4 and Mg

• CuSO4 and Ag

• CuCl2 and Al

• CuSO4 and Fe

To produce metals Na, Mg, Ca in industry, which method is used?

• Electrolysis of saturated chloride salt solution with a partition.

• Using H2 or CO to reduce the corresponding metal oxide at high temperature.

• Using metal K to react with the corresponding chloride salt solution.

• Electrolysis of molten corresponding chloride salt.

The order of reactivity of metals X, Y, Z, T is as follows:

• T, Z, X, Y

• Z, T, X, Y

• Y, X, T, Z

• Z, T, Y, X

When CO gas is passed into a heated tube containing a mixture X of Al2O3, MgO, Fe3O4, CuO, what is the residue Y?

• MgO, Fe3O4, Cu.

• MgO, Fe, Cu.

• Mg, Fe, Cu.

• Mg, Al, Fe, Cu.

How is iron Fe directly produced from Fe2O3?

• Hydraulic method

• Electrolysis of solution.

• Thermal method

• Electrolysis of molten.

Which statement is correct?

• The melting point of metal W is lower than that of metal Al.

• Metal Fe conducts electricity better than metal Ag.

• Metal K is less hard than metal Cr.

• Metal Fe does not react with concentrated hot H2SO4 solution.

What is the unclear experiment?

Which experiment does not occur under normal conditions?

• Add Al powder to a Cl2 gas bottle

• Add Mg powder to a Cu(NO3)2 solution

• Add Fe nail to a dilute H2SO4 solution

• Add Cu powder to an HCl solution

Given the transformation diagram: NaOH Z NaOH E CaCO3. The substances X, Y satisfy the above diagram are respectively:

• NaHCO3, Ca(OH)2

• CO2, CaCl2

• Ca(HCO3)2, Ca(OH)2

• NaHCO3, CaCl2