Answer:
the newspaper one is a chemical change because the chemicals in the paper have reacted with something and turned a different color. the wax one is a physical change because it is a change in the phase of matter, which is always a physical change (still the same substance chemically)
Answer:
light waves a
Explanation:
because there's all kinds of different light in space if you think about it like the bright stars or the bright moon it's kind of like light it just makes sense when it's traveling for space water waves obviously it's not possible that travels through the air or like on a beach sound waves you can't really cure much in space and mechanical waves is pretty much the action of an object or something like that kind of it's pretty much happens on Earth but light waves happen for like asteroids or shooting stars a comments it happens all the time for space so it makes just perfect sense
Reaction equation:
Al(OH)₃ + 3HCl → AlCl₃ + 3H₂O
Moles of Al(OH)₃:
moles = mass/Mr
= 1.51 / (27 + 17 x 3)
= 0.019
Molar ratio Al(OH)₃ : HCl = 1 : 3
Moles of HCl required = 0.019 x 3
=0.057
concentration = moles/volume
volume = 0.057 / 0.1
= 0.57 dm³
= 570 ml
Matter can only me transformed, but not created or destroyed.
Answer:
Carbonated drinks in cans have a headspace to avoid explosion
Explanation:
- When we see in carbonated drinks in cans we can see there is a small amount of space above the liquid level known as the headspace. This space is not a wasted space. The gas filled in the can is compressed highly which when opened comes out with a high pressure with an explosion.
- Therefore, to avoid the carbonated drinks not to explode when shaken the carbonated drinks and the bottled juices have headspace. This means the headspace is not wasted.
