Answer:
H3PO4 is stronger than H2PO4- because
H3PO4 dissociation constant is 6.9×10^-3
H2PO4^- dissociation constant is 6.2×10^-8
Note that
The heating value of standard coal is about 30,080 kJ/kg
1 L of water has a mass of 1.0 kg
The mass of 15 L of water = 15 kg.
The latent heat of vaporization of water is about 2260 kJ/kg,
The energy required to boil 15 L of water is
(2260 kJ/kg)*(15 kg) = 33900 kJ
The mass of coal required to provide this energy is
(33900 kJ)/(30080 kJ/kg) = 1.127 kg
Because 1 kg = 2.205 lb, the mass of coal required is
(1.127 kg)*(2.205 lb/kg) = 2.485 lb
Answer: 2.49 lb (nearest hundredth)
Answer:
poH= -log(oh^-)
= - log (0.500* 10^-11)
= =- log 0.5 + log (10^-11)
= -( -0.30 +(-11))
=+ 11.3
Answer:
states that rock layers with the same unique groupings of fossils are of the same geologic age.
Explanation:
The principle of fossil correlation states that the presence of similar fossils of dead organisms in rock layers indicates that the organisms under investigation must have existed around the same geologic time. This principle can be used in dating the periods when the organism being studied lived.
The geological age system follows a chronological format in tracking the age of an item under study by grouping the time periods that organisms lived into strata.
