In the metric system of units (S.I), the basic unit of length is __

Ostrovityanka [42]

Answer:

17 protons, 20 neutrons, and 17 electrons.

Explanation:

A periodic table can be defined as the standard arrangement of chemical elements by atomic number, electronic configuration and chemical properties in a tabular form.

Generally, a proper representation of the mass number and atomic number of chemical elements is key and very important in chemistry.

Furthermore, as a rule, it should be noted that the mass number (nucleon number) is always larger than the atomic number(number of proton).

The mass number of this neutral atom of Cl-37 is 37 and we know that the atomic number (number of protons) of chlorine is 17. Also, the atomic number of an element is equal to the number of its electrons.

A neutral atom of Cl-37 has 17 protons, 20 neutrons, and 17 electrons.

Hence, a neutral atom of Cl-37 can be identified based on its number of protons because it represent its atomic number, which is what is used to differentiate an atom of an element from the atom of another chemical element.

6 0

2 years ago

How many atoms do I have if I have 2 moles of Hydrogen atoms?

maw [93]

Answer: 6

Explanation: if you multiply the number of moles in the hydrogen atoms by the number of the once displayed and you multiply it by 3 and get the answer 6

6 0

3 years ago

Name two solid liquid and gaseous element at the normal temperature and normal press<br>ure

liubo4ka [24]

Answer:

Solid: calcium and potassium

Liquid: mercury and bromine

Gaseous: oxygen and fluorine

Explanation:

Matter exists in three different states namely: solid, gaseous and liquid. Elements that are found in nature are classified as matter. Since, these elements are grouped as matter, they can either be found as either solids, liquids or gases at normal temperature and pressure.

At normal temperature (20°C or 293K) and pressure (1 atm), the following elements are found to exists in the respective state of matter:

Solid: Calcium (Ca) and potassium (K)

Liquid: Mercury (Hg) and bromine (Br)

Gaseous: Oxygen (O) and fluorine (F)

7 0

3 years ago

A compound is made up of 28 g N, 24 g C, 48 g O, and 8 g H .What is the empirical formula?

vovikov84 [41]

Answer:

$\rm C_2H_8N_2O_3$ .

Explanation:

<h3>Step One: calculate the coefficients. </h3>

Look up the relative atomic mass of these four elements on a modern periodic table:

$\rm C$ : approximately $12$ .
$\rm H$ : approximately $1$ .
$\rm N$ : approximately $14$ .
$\rm O$ : approximately $16$ .

The relative atomic mass of an element is numerically equal to the mass (in grams, $\rm g$ ,) of one mole of atoms of this element.

For example, the relative atomic mass of $\rm C$ is approximately $12$ . Therefore, each mole of $\rm C\!$ atoms would have a mass of $12\; \rm g$ .

This sample contains $24\; \rm g$ of carbon. That would correspond to approximately $\displaystyle \left(\frac{24}{12}\right)\; \rm mol = 2\; \rm mol$ of $\rm C$ atoms.

Similarly, for the other three elements:

$\displaystyle n(\mathrm{H}) \approx \frac{8\; \rm g}{1\; \rm g \cdot mol^{-1}} = 8\; \rm mol$ .

$\displaystyle n(\mathrm{N}) \approx \frac{28\; \rm g}{14\; \rm g \cdot mol^{-1}} = 2\; \rm mol$ .

$\displaystyle n(\mathrm{O}) \approx \frac{48\; \rm g}{16\; \rm g \cdot mol^{-1}} = 3\; \rm mol$ .

Hence, the ratio between these elements in this compound would be:

$n(\mathrm{C}): n(\mathrm{H}): n(\mathrm{N}):n(\mathrm{O}) = 2: 8 : 2 : 3$ .

In the empirical formula of a compound, the coefficients should represent the smallest possible integer ratio between the number of atoms of these elements.

$n(\mathrm{C}): n(\mathrm{H}): n(\mathrm{N}):n(\mathrm{O}) = 2: 8 : 2 : 3$ is indeed the smallest possible integer ratio between the number of atoms of these elements.

<h3>Step Two: arrange the elements in an appropriate order</h3>

Apply the Hill System to arrange these four elements in the empirical formula. In the Hill System:

If carbon, $\rm C$ , is present in this compound, then:

$\rm C$ (carbon) and then $\rm H$ (hydrogen) will be the first two elements listed in the formula (ignore the hydrogen if it is not in the compound.)
The other elements in this compound will be listed in alphabetical order.

If there is no carbon $\rm C$ in this compound, then list all the elements in this compound in alphabetical order.

Both $\rm C$ (carbon) and $\rm H$ (hydrogen) are found in this compound. Therefore, the first element in the list would be $\rm C\!$ . The second would be $\rm H\!$ , followed by $\rm N\!$ and then $\rm O\!$ .

Hence, the empirical formula of this compound would be $\rm C_2H_8N_2O_3$ .

6 0

3 years ago

Which method would be best to separate a mixture of oil and vinegar? separation by filtration distillation separation by density

Snowcat [4.5K]

Answer:

The method which is used to separate a mixture of oil and vinegar is separation by density. Density is defined as the ratio of mass to the amount of matter i.e. volume.

Explanation:

7 0

3 years ago

In the metric system of units (S.I), the basic unit of length is ___?