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4 years ago

How do scientists distinguish between an element and a compound? List two elements and two compounds.

1 answer:

7 0

The difference between an element and a compound is that an element is composed of only one kind of atom while a compound is composed of at least 2 kinds of atoms. The properties of an element and the compound the atoms has to form are different physically and chemically.Example of element are O and H, while compound examples are H2O and H2O2.

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Ne, Ar, and Kr have which properties in common? Group of answer choices

jasenka [17]

Answer:

Ne, Ar, and Kr are gases at STP, unreactive, and are generally monatomic.

Explanation:

they are unreactive and monoatomic and thats why have a very low boiling point.

6 0

3 years ago

What phase of matter has enough kinetic energy to partially overcome the intermolecular attraction between the particles, allowi

cluponka [151]

The answer is; liquid phase

The characteristics described in the question are those of a liquid. The forces between liquid particles are weaker than the forces between solid particles because the particles are further apart. The particles are not held in a fixed position in the structure hence it can flow and take the shape of the container in which it is in.

3 0

3 years ago

Read 2 more answers

Anyone know this <br> Please help me

Olin [163]

Answer:

sorry I don't know

Explanation:

have a great time with your family and friends

6 0

3 years ago

A scientist observed a 5-mL sample of an unknown substance. It is a blue liquid with a density of 1.2 g/cm. the substance reacts

LenaWriter [7]

Characteristic properties can be used to describe and identify the substances, while non-characteristic properties, although can be used to describe the substances, cannot be used to identify them.

Temperature, mass, color, shape and volume are examples of non-characteristic properties.

Density, boiling point, melting point, chemical reactivity are examples of characteristic properties.

List of the properties observed by the scientist:
-----------------------------------------------------------------
Property                                     Type of property
----------------------------------------------------------------
Volume: 5 ml                              non-characteristic
----------------------------------------------------------------
Color: blue                                 non-characteristic
----------------------------------------------------------------
State: liquid                                characteristic
------------------------------------------------------------
density: 1.2 g/cm                        characteristic
------------------------------------------------------------
Reaction: reacts with CO2         characteristic
----------------------------------------------------------

5 0

3 years ago

Suppose you have 75 gas-phase molecules of methanol (CH3OH) at T = 470 K. These molecules are contained in a spherical container

Katarina [22]

Answer:

The average pressure in the container due to these 75 gas molecules is $P=9.72 \times 10^{-16} Pa$

Explanation:

Here Pressure in a container is given as

$P=\frac{1}{3} \rho$

Here

P is the pressure which is to be calculated

ρ is the density of the gas which is to be calculated as below

$\rho =\frac{mass}{Volume of container}$

Here

mass is to be calculated for 75 gas phase molecules as

$m=n_{molecules} \times \frac{1 mol}{6.022 \times 10^{23} molecules} \times \frac{32 g/mol}{1 mol}\\m=75 \times \frac{1 mol}{6.022 \times 10^{23} molecules} \times \frac{32 g/mol}{1 mol}\\m=3.98 \times 10^{-21} g$

Volume of container is 0.5 lts

So density is given as

$\rho =\frac{mass}{Volume of container}\\\rho =\frac{3.98 \times 10^{-21} \times 10^{-3} kg}{0.5 \times 10^{-3} m^3}\\\rho =7.97 \times 10^{-21}\, kg/m^3$

is the mean squared velocity which is given as

$=RMS^2$

Here RMS is the Root Mean Square speed given as 605 m/s so

$=RMS^2\\=(605)^2\\=366025$

Substituting the values in the equation and solving

$P=\frac{1}{3} \rho \\P=\frac{1}{3} \times 7.97 \times 10^{-21} \times 366025\\P=9.72 \times 10^{-16} Pa$

So the average pressure in the container due to these 75 gas molecules is $P=9.72 \times 10^{-16} Pa$

6 0

4 years ago