Answer: D. MIXTURE
Explanation:
It’s important, you first understand the meaning of a pure substance, an element, a compound and a mixture.
A pure substance is a material with a particular composition and consists of only one type of atom or compound. An example is pure sugar.
An element is a substance that cannot be broken down chemically and elements have just one symbol from the periodic table such as Carbon (C), Hydrogen (H).
A compound consists of two or more elements that are bonded chemically. For example, ammonia is a compound with a chemical formula NH3 which means it is means it is made up of 3 moles of Hydrogen and 1 mole of nitrogen.
A mixture contains two or more elements or compounds that are not bonded chemically. It can homogenous or heterogeneous. Examples are salt solution, sand, vinegar.
Vinegar is a mixture of two compounds water and acetic acid and can be separated by physical means because no chemical bond exists between water and acetic acid.
Answer:
0.252 moles
Explanation:
Since 14.1 g of iron is produced and the molar mass of iron is 55.85 g, the number of moles of iron produced is gotten from
n = m/M where m = mass of iron produced = 14.1 g and M = molar mass of iron = 55.85 g/mol
So, n = m/M
n = 14.1 g/55.85 g/mol
n = 0.252 moles of Fe.
So, the theoretical amount of Fe moles produce in the reaction is 0.252 mol
One of the major lab accidents was of fire when a gas was exposed to heat.
<u>Explanation:</u>
The mishaps or the accidents that take place in the laboratory while experimenting are known as the laboratory accidents. Some of the laboratory accidents are chemical spills, fire or explosion, personal injuries and so on.
One of the major lab accidents was of fire when methane gas was exposed to heat. Because of this it led to fire during the experiment. At the time of the experiment, the personal protective equipment worn were the lab gloves, lab coat and the protective eye care. To avoid such kind of accidents, more care and attention should be paid while experimenting. It should be made sure that there are proper equipment in case any accident takes place.
Answer:
The height of the stack will be 
km.
Explanation:
Thickness of the single penny ,t= 1.0 mm
Avogadro number = 
If we stack Avogadro numbers of pennies one top of the other on Earth surface, the height of the pennies can be said to be h.
The height of the stack will be km.
First we need to define some things:
m means meters
mm means millimeters
cm means centimeters
1 m = 100 cm
1 mm = 0.1 cm
They are asking for us to convert 23.6 cm to m and mm
Lets start with 23.6 cm to m:
(the cm's cancel each other out)
Convert 23.6 cm to mm:
(again the cm's cancel out)
Hope this helps!
