Answer:
See explanation
Explanation:
Iodine solution is used to test for starch. A positive test for starch gives a blue-black color.
The fact that the color of the apple remained the same is indicative of the fact that starch was not contained in the apple.
A change in the color of potato indicates the presence of starch in the potato.
The fact that iodine did not react with apple should not be taken to mean that apples contain no starch at all. Starch changes gradually to sugar as fruits ripen. This is why the apple gave a negative test for starch.
Answer:
162.7miles/hr
Explanation:
Given parameters:
Distance covered by the train = 813.5miles
Time taken = 5hours
Unknown:
Speed of the train = ?
Solution:
Speed is a physical quantity.
It is mathematically expressed as;
Speed =
So, input parameters and solve;
Speed = = 162.7miles/hr
Answer:
1.33 L.
Explanation:
- We can use the general law of ideal gas: PV = nRT.
where, P is the pressure of the gas in atm.
V is the volume of the gas in L.
n is the no. of moles of the gas in mol.
R is the general gas constant,
T is the temperature of the gas in K.
- If n and T are constant, and have different values of P and V:
<em>(P₁V₁) = (P₂V₂)</em>
<em></em>
Knowing that:
V₁ = 4.0 L, P₁ = 2.0 atm,
V₂ = ??? L, P₂ = 6.0 atm.
- Applying in the above equation
(P ₁V₁) = (P₂V₂)
<em>∴ V₂ = P ₁V₁/P₂</em> = (2.0 atm)(4.0 L)/(6.0 atm) =<em> 1.33 L.</em>