If ice is warmed and becomes a liquid, the process is endothermic.
The process requires heat in order to proceed. If ice stays in a very cold place, it will not melt unless it's heated. If ice is placed outside where it melts on its own, it gets the heat from the surroundings.
<span>Density is a value for
mass, such as kg, divided by a value for volume, such as m3. Density is a
physical property of a substance that represents the mass of that substance per
unit volume. We calculate as follows:
PV = nRT
PV = mRT/ Molar mass
m/V = P(molar mass)/RT
Density = P(molar mass)/RT
Density = 2.0 ( 30.97 ) / 0.08206 ( 20 + 273.15) = 2.57 g/L <----First option</span>
Explanation:
Two acids we come into contact with in an average week
- Vinegar is an 10% solution of acetic acid
in water. Used in salad dressing and while cooking food. It has a sour taste. - Citric acid present in fruits and vegetables like : lemons, orange, tomatoes etc. It is a weak organic acid with sour taste.
Two bases we come into contact with in an average week.
- Baking soda (
) is used in baking food like: cakes, cookies, breads. Baking soda is one of the ingredient while baking breads and cakes. - Caustic soda (NaOH) is used for preparation of detergents, papers , soaps etc. We use soaps and detergents for washing.
it is a molecule* that can be joined with other molecules that are identical to form a polymer*
key words :
a molecule:
a group of atoms bonded together, representing the smallest fundamental unit of a chemical compound that can take part in a chemical reaction.
a polymer:
a substance that has a molecular structure consisting chiefly or entirely of a large number of similar units bonded together
hope this helped, good luck in future studies !
-A
