Physical change can change a substance by affecting the form of a chemical change.
Examples of physical changes:
Something cut (Paper)
Molded (Bread)
Boiled (Water)
Mixed (Berries and strawberries)
HOPE THIS HELPS YOU! ^_^
SjbwbwnwnnshejskkanNznznbzbzbsbjsjwkekeklrkr
Atomic mass deals with the number of protons and neutrons added together, atomic number deals with protons only, though isotopes can be explained like this, say you had a hydrogen atom it's one proton and one electron if you add a neutron to it, the hydrogen becomes Deuterium which is a isotope of hydrogen it's the same atom just a neutron added to it for a different atomic mass if only slightly changed
The earths gravity attracts the molecules and collects the most near the surface. They all have weight and therefore have more pressure at the surface, as well. As you go higher, the attraction becomes less and these molecules some times fly off into space. This layer of equilibrium has the least of weight or pressure.
The various pressures are measured by precision instruments called barometers or pressure sensors and expressed in inches of mercury or millibars. <span>Air has a weight too, although not very much, If you "pile" the air mile high, the bottom pressure is heavier because of all the air sitting on top of it, therefore the pressure decreases with altitude, because there is less air "piled up" </span>
<span>An analogy would be the same with water.</span>
Planes have these instruments that tells the crew the altitude above sea level they are at when flying.
Remember that density refers to the "mass per unit volume" of an object.
So, if an object had a mass of 100 grams and a volume of 100 milliliters, the density would be 100 grams / 100 ml.
In the question, water on the surface of the scale would add weight, so the mass of the object that you're weighing would appear to be heavier than it really is. If that happens, you'll incorrectly assume that the density is GREATER than it really is
As an example, suppose that there was 5 ml of water on the surface of the scale. Water has a density of 1 gram per milliliter (1 g/ml) so the water would add 5 grams to the object's weight. If we use the example above, the mass of the object would seem to be 105 grams, rather than 100 grams. So, you would calculate:
density = mass / volume
density = 105 grams / 100 ml
density = 1.05 g/ml
The effect on density would be that it would erroneously appear to be greater
Hope this helps!
Good luck
