Answer: Some are solid, some are gaseous, a few are liquid. Some are metallic: they have a peculiar lustre; some are coloured (like sulfur) or colourless. Some have a low density; some have a high density. Some are malleable and ductile; some are brittle. Some conduct electricity and heat well; some don’t.
Many metals tend to have structural uses. Nonmetallic elements less so.
Metals tend to have crystal forms featuring close-packed centro-symmetrical structures. Nonmetallic elements tend to have crystal structures featuring more open and directionally packed structures.
Some are especially toxic; some are essential to life; some are both depending on exposure level.
Most are stable; some are less so.
Some elements are highly reactive; some are almost inert (helium, neon, and argon may be completely inert in ambient conditions).
Many metals have basic oxides; quite a few oxides of nonmetallic elements form acids when they are dissolved in water. Some elements can go both ways.
There are many generalisations you can make about metallic and nonmetallic elements, and quite a few exceptions at the margins.
Explanation:
Answer:
C. Hair dryer
Explanation:
Alternating Current
The other kind of electricity is called alternating current, or AC. Power plants produce this
type of electricity. It is carried by large power lines from the plant to your home. When you
plug a TV, a lamp, or a hair dryer into the wall socket, you are using this type of electricity.
Answer:
The mass of reactants and products for the reaction is this:
- 92 g Na, 32 g O₂, 124 g Na₂O
which is not a choice from the list.
Explanation:
4 moles of Na reacts with 1 mol of oxygen to produce 2 moles of sodium oxide.
Na = 23 g/m
4 moles are (4 . 23) = 92 g
O₂ = 32 g/m
It's a diatomic molecule (each O is 16 g/m)
Na₂O = 62 g/m
2 mol of sodium oxide will be (2 .62) = 124 grams
The mass of reactants and products for the reaction is this:
- 92 g Na, 32 g O₂, 124 g Na₂O
which is not a choice from the list.
The correct answer is A.
Hunger, chemical imbalance, and blood levels are all internal issues. Cat dander on the other hand is not something the body creates or and is something in the environment.
Thus, your answer is A.
