All categories

3 years ago

I'm giving 20 points! please it's for a friend not me

Chemistry

1 answer:

astra-53 [7]3 years ago

6 0

Answer:

Three chemical elements: hydrogen, oxygen, and helium.

The difference between metals and metalloids is: metalloids have properties in between those of the metals and non-metals and are semiconductors.

The periodic table is organized by the elemts atomic number, it goes from the element with the lowest atomic number (which is hydrogen) to the element with the highest atomic number (oganesson)

Explanation:

Hope this helps :)

You might be interested in

When does absorption occur in infrared spectroscopy

Vladimir79 [104]

Answer: hopefully this is right UwU

Explanation: The infrared spectrum of a sample is recorded by passing a beam of infrared light through the sample. When the frequency of the IR is the same as the vibrational frequency of a bond or collection of bonds, absorption occurs. Examination of the transmitted light reveals how much energy was absorbed at each frequency (or wavelength).

5 0

2 years ago

At which of the following temperatures does all molecular motion stop

Kamila [148]

All molecular motion stop at 0 k wich is zero kelvin. At absolute 0 it stops. The temperature of 0 entropy at which all molecular motion stops equals in centigrades to -273.15° C which is the same as 0 in kelvin degrees. Have in mind that temperature is a measure of the average kinetic energy of the molecules in a material.

3 0

3 years ago

Sulfur reacts with oxygen and creates two compounds. Compound A contains 1.34 g of sulfur for every 0.86 g of oxygen. Compound B

spayn [35]

Answer:

The mass ratio of oxygen rounded to the nearest whole no. 3 : 2

Explanation:

According to Law of Multiple proportion when two elements combine to make two or more different compounds, the mass ratio of the two element in the first compound, when divided by the mass ratio of the second compound , form a simple whole number ratio.

Compound A contains 1.34 g of sulfur for every 0.86 g of oxygen

$\frac{1.34}{0.86}= 1.5$

Compound B contains 11.63 g of sulfur for every 10.49 g of oxygen

$\frac{11.643}{10.49}= 1.0$

Ratio of oxygen in each compound

always put the larger number over the smaller number.

$\frac{CompoundA}{Compound B}=\frac{1.5}{1.0}=\frac{3}{2}$

3 0

3 years ago

To determine the freezing point depression of a LiCl solution, Toni adds 0.411 g of LiCl to the sample test tube along with 19.7

Cerrena [4.2K]

Answer:

LiCl = 0.492 m

Explanation:

Molal concentration is the one that indicates the moles of solute that are contained in 1kg of solvent.

Our solute is lithium chloride, LiCl.

Our solvent is distilled water.

We do not have the mass of water, but we know the volume, so we should apply density to determine mass.

Density = mass / volume

Density . volume = mass

1 g/mL . 19.7 mL = 19.7 g

We convert g to kg → 19.7 g . 1 kg / 1000g = 0.0197 kg

Let's determine the moles of LiCl

0.411 g . 1 mol / 42.394 g = 9.69×10⁻³ moles

Molal concentration (m) = 9.69×10⁻³ mol / 0.0197 kg → 0.492 m

7 0

2 years ago

A molecule of carbon dioxide (co2) is formed when one atom of carbon (atomic number 6) is covalently bonded with two atoms of ox

xxMikexx [17]

Carbon must share 4 electrons total with the the two Oxygen atoms in order to fill it's outer electron shell, and each Oxygen atom must share 2 electrons with the Carbon atom to fill their electron shells. Therefore, in total 8 electrons must be shared (4+2+2=8)

4 0

3 years ago