Answer:
For example, a wave with a time period of 2 seconds has a frequency of 1 ÷ 2 = 0.5 Hz. A radio wave has a time period of 0.0000003333333 seconds.
Answer:
A.
Explanation:
The lower the pH the greater the concentration of H+ ions. Hydrochloric acid with a pH of 1 is a strong acid and is highly ionised in solution. It has the most H+ ions
The answer for the following question is option "C".
Option C is not included in the John Dalton's modern theory of an atom.
- "It states atoms of different elements combine to form new compound" but not new elements
Explanation:
According to John's Dalton's modern theory of an atom:
1. All matter is composed of atoms.
2. Atoms cannot be created,destroyed or subdivided in the ordinary chemical reactions.
3. Atoms of one element differ in the properties from atoms of an another element.
(i.e.)Each and every atom of the element has its own unique properties of their own.
4. Atoms of one element combine with the atoms of another element to <u>form new compound.</u>
5. Atoms that make up an element are identical to each other.
Answer:
–500KJ
Explanation:
Data obtained from the question include the following:
Heat of reactant (Hr) = 800KJ
Heat of product (Hp) = 300KJ
Enthalphy change (ΔH) =..?
The enthalphy change is simply defined as the difference between the heat of product and the heat of reactant i.e
Enthalphy change = Heat of product – Heat of reactant
ΔH = Hp – Hr
With the above formula, we can easily calculate the enthalphy change as follow
ΔH = Hp – Hr
ΔH = 300 – 800
ΔH = –500KJ.
Therefore, the overall energy change for the reaction between hydrogen and oxygen shown in the diagram above is –500KJ
