Answer:

Explanation:
<h2><u>Displacement reaction:</u></h2>
- A reaction in which an element displaces or replaces another element of a compound is called a displacement reaction.
<h3><u>Types:</u></h3>
There are 2 types:
<h3><u>1. Single displacement reaction:</u></h3>
- If one element displaces 1 other element of a compound, it is called single displacement reaction.
- <u>Example</u>:

- Here, 1 element (Fe) displaces 1 other element (Cu) of a compound.
<h3><u>2. Double displacement reaction:</u></h3>
- If two elements in two compounds displace one another, it is called double displacement reaction.
- <u>Example:</u>

- Here, Copper and sodium both displace each other.
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Answer:
Explained below.
Explanation:
A substance at low temperature simply means that the average energy of molecular motion in that substance is low while at higher temperature, the average energy of molecular ml tip in that substance is high.
Answer:
1) The elements have filled valence levels.
Explanation:
Since they have filled valence levels, they're stable and don't need to electrons to fill their valence shells since they're already full.
2) False, They do have electrons
3) False, He does have only one electron shell, but going down the periods, every next element have one more electron shell than a preceding one has.
4)False, they're actually the smallest atoms of their respective period
Given:
volume of 0.08 m³
density of 7,840 kg/m³
Required:
force of gravity
Solution:
Find the mass using density
equation.
D = M/V
M = DV
M = (7,840 kg/m³)(0.08 m³)
M = 627.2kg
F = Mg
F = (627.2kg)(9.8m/s2)
F = 6147N
None because Covalent compounds don’t conduct electricity because they are formed between the non metal atoms by sharing of electrons. The Covalent compounds haves no free electrons and also no ions and hence they do not conduct electricity. That is why they do not conduct electricity.