Answer:
Time taken 172.8 years
Explanation:
Given data:
Total amount of strontium-90 = 1000.0 g
Amount left = 15.625 g
Half life of strontium = 28.8 years
Time taken = ?
Solution:
Number of half lives:
At time zero = 1000.0 g
At first half life = 1000.0g/2 = 500 g
At second half life = 500 g/2 = 250 g
At third half life = 250 g/ 2 = 125 g
At 4th half life = 125 g/ 2= 62.5 g
At 5th half life = 62.5 g/2 = 31.25 g
At 6th half life = 31.25 g / 2 = 15.625 g
Time taken:
Time taken = number of half lives × half life
Time taken = 6×28.8 years
Time taken = 172.8 years
Liquid 2 because the lower the density the more it floats and the higher the density the more it sinks. The order from top to bottom is liquid 2, liquid 3, liquid 1
Answer:
Volume is the quantity of three-dimensional
Explanation:
Answer:
2NaOH + CO2 -> Na2CO3 + H2O
1) Find the moles of each substance
2) Determine the limitting reagent
∴ Carbon dioxide is limitting as it has a smaller value.
3) multiply the limiting reagent by the mole ratio of unknown over known
n(H2O ) = 0.3976369007 × 1/2
= 0.1988184504 moles
4) Multiply the number of moles by the molar mass of the substance.
m = 0.1988184504 × (1.008 × 2 + 16.00)
= 0.1988184504 × 18.016
= 3.581913202 g
Explanation:
