Answer:
0.052L
Explanation:
Molarity of a substance, which refers to the molar concentration, is calculated as follows:
Molarity (M) = number of moles (mol) ÷ volume (L)
Mole = mass ÷ molar mass
Molar Mass of AgNO3 since Ag = 108, N = 14, O = 16
108 + 14 + 16(3)
= 108 + 14 + 48
= 170g/mol
Mole = 21.89 g ÷ 170g/mol
Mole = 0.129moles
Using Molarity (M) = number of moles (mol) ÷ volume (L)
Volume = number of moles ÷ molarity
V = 0.129 ÷ 2.50
V = 0.0516
To the correct significant figure i.e. 4s.f, the numerical value of volume = 0.052L
Answer:
Explanation:
- from the Radioactive decay equation ; lnA = ln Ao - kt
- Ao = original amount of substance = 74mg
- where A = is the amount of the substance remaining after time t = 32.7mg,
- k = is a constant that is characteristic of the substance = 2.67 x 10^-1 years^-1
All radioactive substances follow the first order kinetics, as such the rate constant for first order is given as , k = 1/t ln[Ao/A]
- plugging the values in the equation;
- t = 1/0.267 x ln [74/32.7]
- t = 3.05years is the time needed
Answer:
Open spaces in water's solid structure makes its solid state less dense than its liquid state.
Explanation:
- Water unlike other liquids is special. It contracts when cooled, down to a temperature of 4°C but thereafter begins to expand as it reaches 0°C and turns into ice.
- This property is useful for the preservation of marine life in very cold temperatures. During winter, the surface water in water lakes and rivers starts cooling. Upon reaching the temperature of 4°C, the surface water descends to the bottom as it denser.
- This help in the maintenance of temperature of the water at the bottom at 4°C. It is in this layer that marine life is sustained.
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There seem to be 3 major discoveries about particles that year. The first is neutrino oscillation is </span>demonstrated. Next, supernovae observations suggest that the expansion of the universe is accelerating. Time reversal asymmetry is observed for K meson decay