Answer with Explanation:
A "chemical change" occurs when the structure of the molecules change. If there's no change in structure, it is called a "physical change." This also means that a <em>chemical reaction </em>has to occur for something to be considered a chemical change.
Gasoline when used as a fuel is being transformed into other forms of energy. It undergoes a process called <em>"combustion."</em>
When used as a fuel for cars, <em>the gasoline is being burned to produce </em><u><em>heat energy.</em></u> This energy is then converted into <u><em>mechanical energy</em></u> that allows the car to move. Clearly, the gasoline has undergone a chemical change.
Answer:
HNO₃ + NaOH ---> NaNO₃ + H₂O
Explanation:
This reaction appears to be a double-displacement reaction. In these reaction, the cation of one compound is swapped with the cation of another.
As such, the hydrogen cation (H⁺) from HNO₃ is swapped with the sodium cation (Na⁺) of NaOH.
Luckily, all of the cations have a +1 charge and the anions have a -1 charge. This means that no coefficients are necessary to balance the reaction.
The <u>complete balanced </u>equation is:
HNO₃ + NaOH ---> NaNO₃ + H₂O
Answer:
condensation
Explanation:
when gases change to liqud it condenses.This occurs when the temperature is lowered
Answer:
This is site for English speakers. Этот сайт на английском, поэтому вопрос могут удалить
Explanation:
1. 2)
2. 3)
3. 4) Sr
4. 3)
5. 4)
6. 2)
7. 1)
8. 4)
9. 3)
10. 3)
11. SO3, H2SO4, Na2SO4
12.
A) оксид меди (II) 2) CuO
Б) хлорид меди(II) 4) CuCl2
В) сульфит меди (II) 3) CuSO 3
Г) гидроксид меди (II) 1) Cu(OH)2
13.
1. Fe+HCl= б) FeCl 2 +H 2
2.Fe+O2= в) Fe 3 O 4
3. Fe(OH) 3 = г)Fe 2 O 3 +H 2O
4. FeCl 2 +NaOH= а) Fe(OH) 2 +NaCl
14. 2Ca + O2 = 2CaO
CaO + H2O = Ca(OH)2
Ca(OH)2 + 2HCl = CaCl2 + 2H2O
