All categories

3 years ago

MULTIPLE CHOICE QUESTION

Chemistry

1 answer:

zubka84 [21]3 years ago

4 0

Answer:

This question will be answered based on general understanding of how a controlled experiment should be:

The answer is: We must make sure we are testing/changing only one variable, and controling others

Explanation:

A controlled experiment is an experiment in which the independent variable is changed for a particular group called the EXPERIMENTAL group and unchanged for another group called the CONTROL group.

In a controlled experiment, only one variable should be tested while the others should be kept constant in order to have an effective result or outcome. This is the case in this question, the type of music or soil should be unchanged for each plant because the experimenter must make sure that he/she is testing/changing only one variable, and controling others.

You might be interested in

A rock is an example

sveticcg [70]

Answer:

the correct answer is option ( B ) rocks cannot change their volume ,shape, and size

because a solid substance cannot change its, volume, shape and size

Hope it helps you

have a nice day

3 0

3 years ago

Find the energy of a photon of light if the wavelength of the light wave is 6.88 x 10–7m

stepan [7]

Use the formula E=hv, h=plancks constant and v=frequency
use the formula c=v*lambda to find v
the answer will be 2.88*10^-23J

6 0

3 years ago

Carbon tetrachloride can be produced by the following reaction: Suppose 1.20 mol of and 3.60 mol of were placed in a 1.00-L flas

hjlf

The given question is incomplete. The complete question is :

Carbon tetrachloride can be produced by the following reaction:

$CS_2(g)+3Cl_2(g)\rightleftharpoons S_2Cl_2(g)+CCl_4(g)$

Suppose 1.20 mol $CS_2(g)$ of and 3.60 mol of $Cl_2(g)$ were placed in a 1.00-L flask at an unknown temperature. After equilibrium has been achieved, the mixture contains 0.72 mol of $CCl_4$ . Calculate equilibrium constant at the unknown temperature.

Answer: The equilibrium constant at unknown temperature is 0.36

Explanation:

Moles of $CS_2$ = 1.20 mole

Moles of $Cl_2$ = 3.60 mole

Volume of solution = 1.00 L

Initial concentration of $CS_2$ = $\frac{moles}{volume}=\frac{1.20mol}{1L}=1.20M$

Initial concentration of $Cl_2$ = $\frac{moles}{volume}=\frac{3.60mol}{1L}=3.60M$

The given balanced equilibrium reaction is,

$CS_2(g)+3Cl_2(g)\rightleftharpoons S_2Cl_2(g)+CCl_4(g)$

Initial conc. 1.20 M 3.60 M 0 0

At eqm. conc. (1.20-x) M (3.60-3x) M (x) M (x) M

The expression for equilibrium constant for this reaction will be,

$K_c=\frac{[S_2Cl_2]\times [CCl_4]}{[Cl_2]^3[CS_2]}$

Now put all the given values in this expression, we get :

$K_c=\frac{(x)\times (x)}{(3.60-3x)^3\times (1.20-x)}$

Given :Equilibrium concentration of $CCl_4$ , x = $\frac{moles}{volume}=\frac{0.72mol}{1L}=0.72M$

$K_c=\frac{(0.72)\times (0.72)}{(3.60-3\times 0.72)^3\times (1.20-0.72)}$

$K_c=0.36$

Thus equilibrium constant at unknown temperature is 0.36

4 0

3 years ago

Is relative dating an effective way to determine the age of rocks?

JulsSmile [24]

Answer: Read Explanation

Explanation: Index fossils are useful because they tell the relative ages of the rock layers in which they occur. Geologists use particular types of organisms, such as trilobites, as index fossils.

7 0

3 years ago

Read 2 more answers

Cacti and succulents are better adapted

masha68 [24]

Answer:

answer is C

Explanation:

encourage the release of carbon dioxide from the stems

8 0

3 years ago