Help please which substance is not a compound

We are learning about oxygen hydrogen and carbon dioxide, and the question is:

Gre4nikov [31]

I believe it is that most oxides are solids other than these three. i hope this helps.

3 0

3 years ago

A 0.25 M solution of NaCl must be diluted into a 250 mL solution (0.08 M). What volume should be taken from the original solutio

mihalych1998 [28]

Answer:

80ml

Explanation:

you have your initial concentration to be 0.25 mole on your final volume to be 250 ml and your final concentration to be 0.8 0.08 molar you don't have your initial volume sotify your initial volume you use the expression see 1 * 21 equals see two times between you make when when the subject then 1 equals to 2 x 2/3 one you know substitute your values into it to get being one that's your original volume to be at the latest or 80 ml

7 0

4 years ago

Consider the following reaction: 2CH3OH(g)  2CH4(g) + O2(g) ΔH = +252.8 kJ a) Calculate the amount of heat transferred when 24.

denpristay [2]

<u>Answer:</u>

<u>For a:</u> The amount of heat transferred for the given amount of methanol is 94.6736 kJ.

<u>For b:</u> The mass of methane gas produced will be 10.384 g.

<u>Explanation:</u>

For the given chemical reaction:

$2CH_3OH(g)\rightarrow 2CH_4(g)+O_2(g);\Delta H=+252.8kJ$

<u>For a:</u>

To calculate the number of moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given mass}}{\text{Molar mass}}$ ......(1)

Given mass of methanol = 24.0 g

Molar mass of methanol = 32.04 g/mol

Putting values in above equation, we get:

$\text{Moles of methanol}=\frac{24.0g}{32.04g/mol}=0.749mol$

By Stoichiometry of the reaction:

For every 2 moles of methanol, the amount of heat transferred is +252.8 kJ.

So, for every 0.749 moles of methanol, the amount of heat transferred will be = $\frac{252.8}{2}\times 0.749=94.6736kJ$

Hence, the amount of heat transferred for the given amount of methanol is 94.6736 kJ.

<u>For b:</u>

By Stoichiometry of the reaction:

252.8 kJ of energy is absorbed when 2 moles of methane gas is produced.

So, 82.1 kJ of energy will be absorbed when = $\frac{2}{252.8}\times 82.1=0.649mol$ of methane gas is produced.

Now, calculating the mass of methane gas from equation 1, we get:

Molar mass of methane gas = 16 g/mol

Moles of methane gas = 0.649 moles

Putting values in equation 1, we get:

$0.649mol=\frac{\text{Mass of methane gas}}{16g/mol}\\\\\text{Mass of methane}=10.384g$

Hence, the mass of methane gas produced will be 10.384 g.

7 0

4 years ago

a student investigated the factors that affect math grades. Which statement from the lab report best represents a conclusion for

jarptica [38.1K]

A statement from the laboratory report which best represents a conclusion for this investigation is that: D. students who spend less time studying after school get lower math grade.

<h3>What is a research?</h3>

A research is also referred to a study and it can be defined as an investigation which typically involves the process of manipulating an independent variable (the cause), in order to determine or measure the dependent variable (the effect) and reach a logical conclusion with results.

<h3>What is an analytical research report?</h3>

An analytical research report can be defined as a well-crafted and written document that is typically used by a researcher to display a detailed analysis of the information which are obtained through a particular research method.

In this scenario, we can infer and logically deduce that a statement from the laboratory report which best represents a conclusion for this investigation is that the group of students who spend less time studying after school would get lower math grade.

Read more on analytical research here: brainly.com/question/17137042

#SPJ1

4 0

2 years ago

ANSWER ASAP PLEASE I NEED HELP!

Vadim26 [7]

Answer:

If I remember correctly it should be B because it went from Cu^2 to Cu^0

Explanation:

7 0

2 years ago

Help please which substance is not a compound​

Help please which substance is not a compound