Answer:
B. materials change their properties.
Explanation:
In a chemical change, materials often change their properties because a re-arrangement of atoms takes place.
A chemical change is one in which new kind of matter is formed.
It is always accompanied by energy changes.
- Chemical changes are not reversible.
- They lead to the production of new kinds of matter
- It involves mass changes
- Requires considerable amount of energy
Answer:
The mass of C2H2 in the mixture is 0.56gram using the ratio of carbon in the products contributed by the C2H2.
Explanation:
The balanced equation for the reaction is: C3H8 + 2C2H2 + 10O2 >> 7CO2 + 6H2O.
From the reaction, we know that the oxygen was in excess, this will make the Carbon sources the limiting agents in the reaction. The details of the reaction showed that the ratio of water to the carbon dioxide is 1.6:1. This also means that the expected mole of carbon dioxide will be 7/1.6, which is 3.75moles.
The individual balanced equation of reaction is:
C3H3 +5O2 >> 3CO2 + 4H2O
and 2C2H2 + 5O2 >>4CO2 + 2H2O. From this one can quickly tell that the propane is in sufficient supply as it produces 3 moles of CO2 out of the expected 3.75 moles obtained above. Leaving 0.75moles of CO2 to the ethyne.
The mass of ethyne in the mixture will therefore be: 0.75/3.75 X 2.8 = 0.56g.
Answer:
the sun beams down on the pool and heats it up top to bottom the deeper the colder
C is the answer because he wants to know if less force is needed to pull on a slippery surface which reduces friction
