The exact molecular mass for butane (C4H10) is
12.0096*4+1.0079*10=58.1174 which is 58.1 to 3 significant figures.

Proportion of carbon in the compound
12.0096*4: 58.1174
=>
48.0384 : 58.1174

The mass of carbon in 2.50 grams of butane can be obtained by proportion, namely
Mass of carbon
= 2.50 * (48.0384/58.1174)
= 2.0664
= 2.07 g (approximated to 3 significant figures)

4 0

3 years ago

When the following oxidation-reduction occurs, what is the balanced reduction half-reaction after the electrons in both half rea

Lostsunrise [7]

Answer : The balanced reduction half-reaction is:

$3Cu^{2+}+6e^-\rightarrow 3Cu$

Explanation :

Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.

Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. In this, oxidation state of an element increases. Or we can say that in oxidation, the loss of electrons takes place.

Reduction reaction : It is defined as the reaction in which a substance gains electrons. In this, oxidation state of an element decreases. Or we can say that in reduction, the gain of electrons takes place.

The given balanced redox reaction is :

$Al(s)+Cu^{2+}(aq)\rightarrow Al^{3+}(aq)+Cu(s)$

The half oxidation-reduction reactions are:

Oxidation reaction : $Al\rightarrow Al^{3+}+3e^-$

Reduction reaction : $Cu^{2+}+2e^-\rightarrow Cu$

In order to balance the electrons, we multiply the oxidation reaction by 2 and reduction reaction by 3 and then added both equation, we get the balanced redox reaction.

Oxidation reaction : $2Al\rightarrow 2Al^{3+}+6e^-$

Reduction reaction : $3Cu^{2+}+6e^-\rightarrow 3Cu$

The balanced redox reaction will be:

$2Al(s)+3Cu^{2+}(aq)\rightarrow 2Al^{3+}(aq)+3Cu(s)$

Thus, the balanced reduction half-reaction is:

$3Cu^{2+}+6e^-\rightarrow 3Cu$

6 0

3 years ago

Which of the following equations is balanced?

Verizon [17]

answer is B

because both sides have equal numbers of atomos

7 0

3 years ago