Answer:
Chemical changes
Explanation:
a)Burning a piece of charcoal - chemical change
b) Heating copper (ii) carbonate strongly - chemical change
c) Heating Zinc oxide strongly - chemical change
The given types of reaction indicates chemical changes. A chemical change is one in which a new kind of matter is formed. It is always accompanied by energy changes. The process is not easily reversible and hence, it is a permanent procedure.
Burning of charcoal produces a new kind of produces in the combustion process.
Both heating of copper(ii)carbonate strongly and zinc oxide will lead to a decomposition reaction in which new compounds are formed.
Answer:
because mariah carey wrote it
Explanation:
she also made a song out of it!
It will be B.) A force equal to the force keeping the object at rest, but in the opposite direction.
Answer:
0.497 moles/L
Explanation:
The reaction that takes place is:
- C₃H₆O₃ + NaOH → C₃H₅ONa + H₂O
First we c<u>alculate the moles of lactic acid in 0,821 g</u>, using its molar mass:
- 0,821 g ÷ 90 g/mol = 9,122x10⁻³mol lactic acid
<em>One mole of lactic acid reacts with one mole of sodium hydroxide</em> (it is a monoprotic acid), so in 18,34 mL of NaOH solution there are 9,122x10⁻³moles of NaOH:
- 18.34 mL ÷ 1000 = 0,01834 L
- 9,122x10⁻³mol ÷ 0,01834 L = 0.497 moles/L