Answer:
The molarity is 0.203 M
Explanation:
Using the formula C(oxi) x V(oxi) / [C(red) x V(red)] = N(oxi) / N(red)
Where oxi and red means reducing agent and oxidising agent respectively.
C = Concentration, V = Volume and N = number of moles.
C(oxi) = 0.5 M
V(oxi) = mL
C(red) = ?
V(red) = 30mL
Equation of reaction = 2K2S2O3 + KI3 = K2S4O6 + 3KI
so N(red) = 1 , N(oxi) = 2
from the equation above,
C(red) = 0.5 x 25 x 1 / (2 x 30)
= 0.203 M.
Answer: Time taken by a sound impulse to travel through an aluminum rod 25 kilometers long is 4.9 seconds.
Solution:
Length of aluminium rod = 25 km = 25000 m (1 km=1000 m)
Time taken by sound to travel through aluminium = 5100 m/s (from the table given)
time taken =
Hence, the correct option is 4.9 seconds.
Answer:
4.28x10^24 molecules
Explanation:
From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules. From the above, we understood that 1mole of H2O also contains 6.02x10^23 molecules.
1mole of H2O = (2x1) + 16 = 2 + 16 = 18g
Now, if 18g of H2O contains 6.02x10^23 molecules,
Then 128g of H2O will contain = (128x 6.02x10^23) /18 = 4.28x10^24 molecules
OPTION B & C are the answers....
D will because water just turns from liquid to a gas by adding heat. That is a physical change. The other equations are chemical changes.
