Chemistry, 08.10.2019 00:50 mikisims

8. a student passes a magnet over 10 g of a powder. four grams of the powder stick to the magnet, while 6 g do not. which of these identifies the substance? *
element
compound
mixture
solution

Answers: 3

Show answers

Answers

Answer from: only1cache

mixture

Explanation:

The properties of the components of substance are different. One component has magnetic properties, another does not. So, we have at least 2 individual substances that were mixed together. So, we have a mixture.

Answer from: pamelaacuna

Option (c) is the correct answer.

Explanation:

An element is defined as a substance which can never be broken down into simpler substances.

For example, sodium is a metal and it contains only atoms of sodium.

A compound is defined as a substance that contains two or more different elements that are chemically combined together in a fixed ratio by mass.

For example, KCl is a compound in which atoms are present in 1:1 ratio.

A mixture is defined as a substance in which two or more number of different substances are mixed together. Particles of a mixture never combine chemically to each other.

A solution is also known as a homogeneous mixture because in it the solute particles are evenly distributed.

So, when a student passes a magnet over 10 g of a powder. Four grams of the powder stick to the magnet, while 6 g do not then this means that particles were not chemically combined together and they are also not evenly distributed into the solution.

Thus, we can conclude that mixture identifies the substance.

Answer from: Quest

answer: the value of enthalpy change will be -152.80 kj.

solution:

pressure = 1atm , temperature = $25^oc$ = 298 k $)0^oc=273kelvins$

$o_3+3no\rightarrow 3no_2,\delta h_{reaction}=? [/)</p><p>[tex]\delta h_{no}=90.4kj/mol$

$\delta h_{no_2}=33.85kj/mol$

$\delta h_{o_3}=142.2kj/mol$

$\delta h_{reaction}=\sum \delta h_{products}-\sum\delta h_{reactants}=3\times\delta h_{no_2}-(3\times \delta h_{no}+\delta h_{o_3})$

$\delta h_{reaction}=33.85-(90.4+142.2)=-311.85kj/mol$

given that pressure and temperature are same in both gases , the number of moles of both gases can be determined by the ideal gas equation.

$v_{no}=12.00 l,v_{o_3}=8.50 l$

$pv_{no}=n_{no}rt=1atm \times 12.00 l=n_{no}\times 0.0821 atml/k mol \times 298 k$

$n_{no}=0.49 moles$

$pv_{o_3}=n_{o_3}rt=1atm \times 8.50 l=n_{o_3}\times 0.0821 atml/k mol \times 298 k$

$n_{o_3}=0.34 moles$

according to reaction 3 moles no are reacting with 1 mol of $o_3$ ,then 0.49 mol of no will react with $\frac{1}{3}\times 0.49$ moles of ozone that is 0.16 moles of ozone. since, no is limiting reagent and $o_3$ is an excessive reagent.

enthalpy change for the reaction between the given volumes of the gases is :

$\delta h_{reaction}\times \text{moles of no}=-311.85kj/mol\times 0.49 mol=-152.80kj/mol$

Answer from: Quest

because of all the things that happen around the us, many people get into arguments which sadly could get physical, but we should actually make a change for that.

Another question on Chemistry

Chemistry, 22.06.2019 12:00

From the options provided for each element below, choose the properties that it may have based on its location in the periodic table fluorine (f): highly reactive nonmetal shiny a conductor

Answers: 1

Answer

Chemistry, 22.06.2019 15:30

What best discribes the relationship between wavelength and frequency in a electromagnetic wave

Answers: 1

Answer

Chemistry, 23.06.2019 01:00

Who examines and coordinates the cleanup of polluted sites?

Answers: 2

Answer

Chemistry, 23.06.2019 01:30

What happens to the concentration of hydronium ions as the ph of a solution increases? a. hydronium ion concentration stays the same b. hydronium ion concentration decreases c. hydronium ion concentration increases

Answers: 1

Answer

You know the right answer?

8. a student passes a magnet over 10 g of a powder. four grams of the powder stick to the magnet, wh...

Questions