A. 6
B. 8
C. 10
D. 4
A. Flrorine
B. Chlorine
C. Bromine
D. Iodine
A. Single covalent bond
B. Hydrogen bond
C. Double covalent bond
D. Coordinate covalent bond
A. 6.02 x 1023 C/kg
B. 1.7588 x 1020 C/kg
C. 9.1095 x 10-31 C/kg
D. 1.7588 x 1011 C/kg
Which of the following is a substance?
A. Sea water
B. Brass
C. Tape water
D. Graphite
E. Sand
In chemistry, a substance refers to a matter which has specific composition and specific properties which do not change. A substance can be an element or a compound. A substance typically has a constant composition, which can not be separated by physical methods. Seawater and sand are not substances, because they have varied compositions and their components can be separated by physical methods.
A. Hydrogen & Water
B. Hydrogen & Carbon dioxide
C. Hydrogen & Methane
D. Carbonmonoxdide & water
A. C12H22O11
B. C6H10O5
C. (C6H10O5)n
D. C6H12O6