Answer: The correct statement is (A new substance is formed and the process can usually NOT be undone.)
Explanation:
A chemical reaction is simply defined as the reaction between two or more elements in which a new substance is formed and the process can usually not be undone. Different types of chemical reaction includes:
-- combination reaction: this occurs when two or more reactants form a product. For example: In the burning of coal, It combines with oxygen to produce carbon dioxide. Also in the burning of wood, carbon dioxide is given off and ashes are formed. Because new substance is being formed, they often can't be undone. The ashes formed can't be changed back into wood. Other types of chemical reaction are listed below.
-- Decomposition reaction
-- Single displacement reaction
-- Double displacement reaction
-- combustion reaction
-- Redox reaction
For the product of a chemical reaction to be undone (reversed), it has to undergo another chemical process different from the one that produced it.
Answer:
CH2FCOOH > CH2ClCOOH > CH2BrCOOH > CH3COOH
Explanation:
CH2FCOOH > CH2ClCOOH > CH2BrCOOH > CH3COOH
More electronegative atom of halogen is , stronger acid will be.
Answer:
C) to show that atoms are conserved in chemical reactions
Explanation:
When writing a chemical reaction, we should always consider the Mass Conservation Law, which basically states that; in an isolated system; the total mass should remain constant, this is, the total mass of the reactives should be equal to the total mass of the products
For this case, we should add the apporpiate coefficients in order to be in compliance with this law:
2H₂ + O₂ → 2H₂O
So, we can check the above statement:
For reactives (left side):
4H
2O
For product (right side):
4H
2O
Answer:
0.444 mol/L
Explanation:
First step is to find the number of moles of oxalic acid.
n(oxalic acid) = 
Now use the molar ratio to find how many moles of NaOH would be required to neutralize
of oxalic acid.
n(oxalic acid): n(potassium hydroxide)
1 : 2 (we get this from the balanced equation)
: x
x = 0.0111 mol
Now to calculate what concentration of KOH that would be in 25 mL of water:

<u>Answer: </u>The equation which is wrong is 
<u>Explanation:</u>
For the given reaction:

The expression for
is given by:
![K_c=\frac{1}{[O_2]^3}](https://tex.z-dn.net/?f=K_c%3D%5Cfrac%7B1%7D%7B%5BO_2%5D%5E3%7D)
![K_p=\frac{1}{[O_2]^3}](https://tex.z-dn.net/?f=K_p%3D%5Cfrac%7B1%7D%7B%5BO_2%5D%5E3%7D)
The concentration of solids are taken to be 1, only concentration of gases and liquid states are taken. The pressure of only gases are taken.
Relationship between
is given by the expression:

where,
= number of moles of gaseous products - number of moles of gaseous reactants
R = gas constant
T= temperature
For the above reaction,
= number of moles of gaseous products - number of moles of gaseous reactants = 0 - 3 = -3
Hence, the expression for
is:

Therefore, the equation which is wrong is 