Answer:
Scientific theories are testable and make falsifiable predictions. They describe the causes of a particular natural phenomenon and are used to explain and predict aspects of the physical universe or specific areas of inquiry (for example, electricity, chemistry, and astronomy).
A good theory in the theoretical sense is (1) consistent with empirical observations; is (2) precise, (3) parsimonious, (4) explanatorily broad, and (5) falsifiable; and (6) promotes scientific progress (among others; Table 1.1).
Answer:
Particles of matter possess energy called kinetic energy.
Solid cannot be compressed, but gases are highly compressible.
The Kinetic energy of molecules of gases is very large & solids the least.
On heating a sublimable liquid, the molecules break free & escape from the surface of the solid directly into vapour.
Particles of matter move more rapidly on the application of heat
<span>C. A completely new substance is formed.</span>
Answer:
moles SO42- = 0.0500 L x 0.20 M=0.010
moles Ba2+ = 0.0500 L x 0.10 M = 0.0050
Ba2+ + SO42- = BaSO4 (s)
moles SO42- in excess = 0.010 - 0.0050=0.0050
total volume = 100 mL = 0.100 L
[SO42-]= 0.0050/0.100= 0.050 M
[Na2SO4] = 2 /2 = 1 M
moles Na2SO4 = 2 M x 0.500 L = 0.500
mass Na2SO4 = 0.500 x 142 g/mol=71.0 g
moles MgBr2 = 46 /184 =0.25
moles Br- = 0.25 x 2 = 0.50
[Br-]= 0.50 / 0.50 L = 1 M