Answer : Molecules.
Explanation : Elements are the class of pure substances that cannot be physically separated; but they are made up of the same atoms of the same elements. When two or more elements are combined chemically with a chemical bond they become physically inseparable; which is called as a Molecule. Therefore, the term which represents represents a pure substance that can be separated chemically, but cannot be separated physically, that is made up of two or more different atoms is a molecule.
A compound is made up many different molecules. The main difference between the compound and the molecule is that a compound must have at least two different elements. So, it can be said that a compound is a type of molecule.
Mixtures are made up of different compounds which can be physically separated.
Answer:
The answer to your question is: ΔHrxm = -23.9 kJ
Explanation:
Data:
2Fe(s)+3/2O2(g)→Fe2O3(s), ΔH = -824.2 kJ (1)
CO(g)+1/2O2(g)→CO2(g) ΔH = -282.7 kJ (2)
Reaction:
Fe2O3(s)+3CO(g)→2Fe(s)+3CO2(g)
We invert (1) and change the sign of ΔH
Fe2O3(s) → 2Fe(s)+3/2O2(g) ΔH = 824.2 kJ
We multiply (2) by 3
3( CO(g)+1/2O2(g)→CO2(g) ΔH = -282.7 kJ) (2)
3CO(g)+3/2O2(g)→3CO2(g) ΔH = -848.1 kJ
We add (1) and (2)
Fe2O3(s) → 2Fe(s)+3/2O2(g) ΔH = 824.2 kJ
3CO(g)+3/2O2(g)→3CO2(g) ΔH = -848.1 kJ
Fe2O3(s) + 3CO(g)+3/2O2(g) → 2Fe(s)+3/2O2 + 3CO2(g)
Simplify
Fe2O3(s)+3CO(g)→2Fe(s)+3CO2(g) and ΔHrxm = -23.9 kJ
Answer:
Xà phòng hoá hoàn toàn 40,8 gam phenyl axetat trong dung dịch NaOH dư. Cô cạn dung dịch sau phản ứng thu được khối lượng muối làA. 59,4 g. B. 24,6 g. C. 39,6 g.D. 64,8 g.
The shape would be a square i think but im not sure
Answer:
Hydrogen may not be advantageous as a fuel because...
- Its expensive
- Its difficult to store
- Its highly flammable
- Its dependent on fossil fuels
Explanation:
Its expensive - Not only is hydrogen gas expensive, but it also takes a lot of work to free from other elements. It is both expensive and time-consuming to produce.
Its difficult to store - Moving hydrogen is not an easy task. Moving anything more than small amounts of hydrogen was also very expensive, making it impractical.
Its highly flammable - When exposed to the atmosphere, hydrogen could potentially form explosive mixtures.
Its dependent on fossil fuels - Hydrogen energy itself is renewable. However, the process of separating it from oxygen uses non-renewable sources such as coal and oil.
~Hope this Helps!~