Answer : The time passed in years is 
Explanation :
Half-life = 5730 years
First we have to calculate the rate constant, we use the formula :



Now we have to calculate the time passed.
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = time passed by the sample = ?
a = let initial amount of the reactant = X g
a - x = amount left after decay process = 
Now put all the given values in above equation, we get


Therefore, the time passed in years is 
Phenolphthalein
In acid it is colourless and in water also colourless
<u>Advantages of Nuclear Fission</u>
-
Nuclear fission provides cheapest energy . Almost 10% of electricity used in the world is obtained from the fission reaction
- It offers a low-emission energy solution since there is no carbon dioxide gas emitted during the nuclear fission reaction
- A well controlled and maintained nuclear reactor can produce energy for 36 to 40 months so works for .
- It is a reliable source of energy as energy is obtained from uranium which is available is plenty.
- It provides very concentrations of energy as it can provide large amount of energy from small amount of fuel.
- The reaction gives less annual mortality rate of any energy resource with 90 deaths per trillion kilowatt hours
<u>Disadvantages of Nuclear Fission
</u>
- It is dangerous and also explosive.
- It creates harmful and radioactive waste products.
- It is not a renewable energy resource like solar and wind energy
- It can develop long-term health issues for people exposed to then radioactive waves.
- It involves high cost in installation of the reactors.
Answer: 43.3 l
Explanation:
1) Chemical equation:
2 Li(s) + 2 H₂O (l) → 2LiOH(aq) + H₂ (g)
2) Mole ratios:
2 mol Li : 2 mol H₂O : 2 mol LiOH : 1 mol H₂
3) Number of moles of Li that react
n = mass in grams / atomic mass = 24.6g / 6.941 g/mol = 3.54 moles
4) Yield
Proportion:
2 mol Li / 1 mol H₂ = 3.54 mol Li/ x
⇒ x = 3.54 mol Li × 1 mol H / 2 mol Li = 1.77 mol H₂
4) Ideal gas equation
PV = nRT ⇒ V = nRT / P
V = 1.77 mol × 0.0821 [atm×l / (mol×K)] × 301 K / 1.01 atm = 43.3 l
V = 43.3 l ← answer
Answer:
11.19% hydrogen and 88.81% oxygen
Explanation: