A sample of an iron and oxygen ore has a mass of 35.8 grams. The iron in the compound has a mass of 27.9 grams. What is the percent iron in the ore?
A. 74% Fe
B. 75% Fe
C. 77% Fe
D. 78% Fe
Chemistry Mcqs
A compound is determined to have an emperical formula of C2H6O and a molar mass of 138 g/mole. What is the molecular formula?
A compound is determined to have an emperical formula of C2H6O and a molar mass of 138 g/mole. What is the molecular formula?
A. C2H6O
B. C6H18O3
C. C6H12O6
D. C2H5O
A substance is analyzed and found to have an emperical formula of CH2 and a molar mass of 56g/mole. What is the molecular formula of the compound?
A substance is analyzed and found to have an emperical formula of CH2 and a molar mass of 56g/mole. What is the molecular formula of the compound?
A. C2H4
B. C3H6
C. C4H8
D. C5H10
The number of atoms present in 21.6 gram of silver (atomic weight = 108) are same as the molecules in__________?
The number of atoms present in 21.6 gram of silver (atomic weight = 108) are same as the molecules in__________?
A. 1.8 gram of H2O
B. 12 moles of KMnO4
C. 0.6N H2SO4
D. 4.6 gram of C2H5OH
Which of the following phenomenon is considered responsible for Global Warming?
Which of the following phenomenon is considered responsible for Global Warming?
A. Greenhouse effect
B. Fire in coal mines
C. Dry farming
D. Monsoon
The number of d-electrons in Fe2+ (Z = 26) is not equal to that of____________?
The number of d-electrons in Fe2+ (Z = 26) is not equal to that of____________?
A. p-electrons in Ne(Z = 10)
B. s-electrons in Mg(Z = 12)
C. d-electrons in Fe(Z = 26)
D. p-electrons in CI(Z = 17)
The metallurgical process in which a metal is obtained in a fused state is called__________?
The metallurgical process in which a metal is obtained in a fused state is called__________?
A. smelting
B. roasting
C. calcinations
D. froth floatation
The molecules of which gas have highest speed?
The molecules of which gas have highest speed?
A. H2 at -73oC
B. CH4 at 300 K
C. N2 at 1,027oC
D. O2 at 0oC
The law which states that the amount of gas dissolved in a liquid is proportional to its partial pressure is___________?
The law which states that the amount of gas dissolved in a liquid is proportional to its partial pressure is___________?
A. Dalton’s law
B. Gay Lussac’s law
C. Henry’s law
D. Raoult’s law
The main buffer system of the human blood is____________?
The main buffer system of the human blood is____________?
A. H2CO3 – HCO3
B. H2CO3 – CO32-
C. CH3COOH – CH3COO–
D. NH2CONH2 – NH2CONH+