All categories

3 years ago

Which of the following represents a chemical change?

Chemistry

1 answer:

Nikitich [7]3 years ago

7 0

Answer:

Option B : burning of wood

Explanation:

Chemical change is a change where a new substance is created like when you will bur wood you get ash this is a new substance, so burning of wood is a chemical change.

You might be interested in

What is the numbers to the C02

andriy [413]

Answer:

413.20 ppm

Explanation:

4 0

3 years ago

In ADEF, the measure of F=90°, the measure of ZD=10, and EF = 94 feet. Find the

Flauer [41]

Answer:

answer. the measure. is f=90 the equbaliint is 180

Explanation:

yan ang sagot ko

3 0

3 years ago

Balance each of the following redox reactions occurring in basic solution.MnO−4(aq)+Br−(aq)→MnO2(s)+BrO−3(aq)Express your answer

Ahat [919]

Answer : The balanced chemical equation is,

$2MnO_4^-(aq)+Br^-(aq)+H_2O(l)\rightarrow 2MnO_2(s)+BrO_3^-(aq)+2OH^-(aq)$

Explanation :

Rules for the balanced chemical equation in basic solution are :

First we have to write into the two half-reactions.
Now balance the main atoms in the reaction.
Now balance the hydrogen and oxygen atoms on both the sides of the reaction.
If the oxygen atoms are not balanced on both the sides then adding water molecules at that side where the more number of oxygen are present.
If the hydrogen atoms are not balanced on both the sides then adding hydroxide ion $(OH^-)$ at that side where the less number of hydrogen are present.
Now balance the charge.

The half reactions in the basic solution are :

Reduction : $MnO_4^-(aq)+2H_2O(l)+3e^-\rightarrow MnO_2(s)+4OH^-(aq)$ ......(1)

Oxidation : $Br^-(aq)+6OH^-(aq)\rightarrow BrO_3^-(aq)+3H_2O(l)+6e^-$ .......(2)

Now multiply the equation (1) by 2 and then added both equation, we get the balanced redox reaction.

The balanced chemical equation in a basic solution will be,

$2MnO_4^-(aq)+Br^-(aq)+H_2O(l)\rightarrow 2MnO_2(s)+BrO_3^-(aq)+2OH^-(aq)$

8 0

3 years ago

Which substance is one that cannot be separated or broken down into simpler substances by chemical means? (Element, pure)

Y_Kistochka [10]

Answer:

gold wire (Au)

Explanation:

A substance that cannot be separated or broken down into simpler substances by chemical means is an element.

Between the given options only gold wire is an element, Au.

A way of knowing that it is an element is noticing that its formula is a single symbol which corresponds to an element found in the periodic table, unlike a combination of said symbols (like NaCl or H₂O).

5 0

3 years ago

How many moles of carbon are in 3.7 moles of C 8 H11 NO2

Dafna1 [17]

In every molecule of $C_{8} H_{11}NO_2$ there is 8 atoms of Carbon.

IF we have 3.7 moles of $C_{8} H_{11}NO_2$ to find the number of moles of Carbon, just multiply by 8

3.7 * 8 = 29.6 mol Carbon

6 0

3 years ago