Answer: The age of the tool is 15539 years
Explanation:
Expression for rate law for first order kinetics is given by:
where,
k = rate constant
t = age of sample
a = let initial amount of the reactant = 100
a - x = amount left after decay process =
a) for completion of half life:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.
b) for 15.5 % of original amount
Thus age of the tool is 15539 years
<span>0.06355391 mol
The balanced equation for the reaction is
Na2B4O7*10H2O + 2 HNO3 = 2 NaNO3 + 4 H3BO3 + 5 H2O
So for each mole of Borax to neutralize, it takes 2 moles of HNO3.
Calculate number of moles of Borax
0.2619 g / 381.372 g/mol = 0.0006867 mol
Moles of HNO3 used = 0.0006867 mol * 2 = 0.0013734 mol
Molarity is defined as moles per liter so divide the number of moles used by the volume in liters. So
0.0013734 / 0.02161 = 0.06355391 mol</span>
H2O is the Bronsted-Lowry base because it accepts the hydrogen ion to become H3O after the reaction is complete.
Answer:
Washing Clothes & Dissolving Sugar
Explanation:
Think about each application:
1) Washing clothes: You kind of need water to do this, or not much washing can be done.
2) Linking brake pedals to the brake pads: You don't need any liquids for this. You need solids.
3) Deodorizing a room: You would problem choose an aerosol, which is sprayed, thus a gas.
4) Carving a sculpture: You would use solid tool and a sold sculpture.
5) Dissolving sugar: You need a liquid to dissolve sugar!
6) Painting a wall: Perhaps, you COULD say that the paint is a liquid... but I'm not sure if that really counts. I believe this application would still be solids.
7) A gear for a machine is a solid!