An atom has 5 protons, 6 neutrons, and 5 electrons. What is the charge of the atom's nucleus?

A solution is formed by mixing 15.2 g KOH into

nikitadnepr [17]

Answer:

There are approximately $0.271\; \rm mol$ of formula units in that $\rm 15.2\; g$ of $\rm KOH$ (the solute of this solution.)

Explanation:

A solution includes two substances: the solute and the solvent. Note the solution here contains significantly more water than $\rm KOH$ . Hence, assume that water is the solvent (as it is in many other solutions.)

The (molar) formula mass of $\rm KOH$ is necessary for finding the number of moles of

One $\rm K$ atom,
One $\rm O$ atom, and
One $\rm H$ atom.

The formula mass of $\rm KOH$ will thus be the sum of:

The mass of one mole of $\rm K$ atoms,
The mass of one mole of $\rm O$ atoms, and
The mass of one mole of $\rm H$ atoms.

On the other hand, the mass (in grams) of one mole of atoms of an element is (numerically) the same as its relative atomic mass. The relative atomic mass data can be found on most modern periodic tables.

Relative atomic mass data from a modern periodic table:

$\rm K$ : $39.098$ .
$\rm O$ : $15.999$ .
$\rm H$ : $1.008$ .

For example, the relative atomic mass of $\rm K$ (potassium, atomic number $19$ ) is $39.098$ (3 sig. fig.) Hence, the mass of one mole of

The formula mass of $\rm KOH$ is the sum of these three masses:

$\begin{aligned}& M(\mathrm{KOH}) \\ &\approx 39.098 + 15.999 + 1.008 \\ &= 56.105\; \rm g \cdot mol^{-1}\end{aligned}$ .

The number of moles of $\rm KOH$ formula units in this $15.2\; \rm g$ sample would be:

$\begin{aligned}n &= \frac{m(\mathrm{KOH})}{M(\mathrm{KOH})} \\ &\approx \frac{15.2\; \rm g}{56.105\; \rm g \cdot mol^{-1}} \approx 0.271\; \rm mol \end{aligned}$ .

6 0

3 years ago

Which statement is true about word equations with regards to chemical reactions?

Akimi4 [234]

The total mass of the reactants equals the total mass of the products

6 0

2 years ago

How do the ongoing processes of scientific investigation and technological design interact with each other?

Yuri [45]

Answer is
<span>a.Scientific investigation discovers new information that can be used in technological design, and technological design provides new products that can further scientific investigation.

Scientific investigation helps to discover new information, such as greater insight into how the world works. This information can be applied to technological design, illuminating new ways to do things. </span>

4 0

3 years ago

Read 2 more answers

Describe the contributions made by Oparin, Haldane, Miller, and Urey toward understanding the origin of organic molecules.

balu736 [363]

Answer:

The theory of Oparin and Haldane was based on the fact that the primitive atmosphere was very different from the current atmosphere, since energy was abundant on the young planet. Both proposed that the appearance of life was preceded by a period they called "chemical evolution."

On the other hand, Miller Urey made an experiment where it was shown that some organic components were formed spontaneously if they were simulating the conditions of the Earth's early atmosphere.

Explanation:

The first hypotheses about the origin of life on Earth were suggested by Oparin and Haldane, who worked independently. Oparin presented his ideas on the origin of life in the year of 1922 by publishing them in the year of 1924. For his part, Haldane published similar ideas in 1929, however, Haldane gave priority to Oparin in the formulation of the theory.

Oparin based his hypotheses using a model he called "coacervates", which are colloidal systems formed by macromolecules that formed in aqueous media and would have evolved to form cells with membranes. According to Oparin, living beings modified the primitive atmosphere and this would have prevented, the formation of life from inorganic substances.

The Miller and Urey experiments helped reinforce the theory that the first way of life was created spontaneously through chemical reactions. However, there are still many scientists who are not convinced.

8 0

3 years ago

Semasa proses pengewapan, cecair bertukar menjadi gas. Apakah yang berlaku kepada zarah dalam cecair??

katovenus [111]

Can you translate in english i can’t understand this

4 0

3 years ago