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2 years ago

What is called a measurement and does involve a number and unit in chemistry?

Chemistry

1 answer:

marta [7]2 years ago

3 0

Answer:

1.1: Taking Measurements. Chemists measure the properties of matter and express these measurements as quantities. A quantity is an amount of something and consists of a number and a unit. The number tells us how many (or how much), and the unit tells us what the scale of measurement is.

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Explain why it is necessary to balance chemical equations in terms of maintaining equilibrium. How can you tell when a chemical

LUCKY_DIMON [66]

Answer:

See explanation.

Explanation:

Hello,

In this case, we say that chemical reactions are governed by the law of conservation of mass, which states that matter cannot be neither created nor destroyed by transformed, for that reason, we need to balance chemical reactions in order to ensure all the atoms to be in the same quantity at both reactants and products.

Moreover, equilibrium is defined as such condition at which the concentration of both reactants and products stop changing over the time so they become constant as well as their null reaction rate.

A widely acknowledged reaction is the HABER one which consists on the synthesis of ammonia by using elemental nitrogen and hydrogen:

$N_2(g)+3H_2(g)\rightleftharpoons 2NH_3(g)$

In such reaction, we have two nitrogens at both reatants and products and six hydrogens at at both reatants and products for us to obey the law of conservation of mass. Furthermore, as the time goes by, nitrogen reacts with hydrogen, nonetheless, they do not react indefinitely, they have a limit that is equilibrium, so their moles stop being consumed and remain unchanged as well as the produced moles of ammonia.

Best regards.

7 0

3 years ago

A compound is found to contain 50. 05% sulfur and 49. 95% oxygen by mass. What is the empirical formula for this compound? SO S2

jekas [21]

The empirical formula for the given compound has been $\rm SO_2$ . Thus, option C is correct.

The empirical formula has been the whole unit ratio of the elements in the formula unit.

<h3>Computation for the Empirical formula</h3>

The given mass of Sulfur has been, 50.05 g

The given mass of oxygen has been 49.95 g.

The moles of elements in the sample has been given by:

$\rm Moles=\dfrac{Mass}{Molar\;mass}$

Moles of Sulfur:

$\rm Moles\;S=\dfrac{50.05}{32}\\
 Moles\;S=1.56\;mol$

The moles of sulfur in the unit has been 1.56 mol.

Moles of Oxygen:

$\rm Moles\;O=\dfrac{49.95}{16} \\
Moles\;O=3.12\;mol$

The moles of oxygen in the unit has been 3.12 mol.

The empirical formula unit has been given as:

$\rm S_{1.56}O_{3.12}=SO_2$

Thus, the empirical formula for the given compound has been $\rm SO_2$ . Thus, option C is correct.

Learn more about empirical formula, here:

brainly.com/question/11588623

8 0

2 years ago

Which of the following claims may be made based on your observations? (You will recieve negative points for wrong answers.)

Ostrovityanka [42]

Answer:

D, E and F

Explanation:

About tetrachloro cobalt complexes, the following facts have been observed

Color of the tetrachloro cobalt complexes is blue.
They do not decompose on heating that means synthesis of tetra chloro is endothermic.

About hexa aqua cobalt complexes, the following facts have been observed

Color of the hexa aqua cobalt complexes is pink color.
They decompose on heating and remain stable on cooling that means process of synthesis of hexa aqua cobalt complexes is exothermic.

Based on above, the correct statements are:

The correct is chloro cobalt complex is blue and aqua cobalt

complex is pink.

The chloro complex is favored by heating.

If the chloro complex is a product, then the reaction must be endothermic.

The correct options are D, E and F.

8 0

3 years ago

The expected o-c-h angle in this molecule is degrees. the expected hybridization at the central carbon is

WINSTONCH [101]

Each neutral carbon atom contains four valence electrons and may form up to four electron domains. Possible hybridizations include

$sp^{3}$ , four electron domains, as in ethane $\text{C}_2\text{H}_6$
$sp^{2}$ , three electron domains, as in ethene $\text{C}_2\text{H}_4$
$sp$ , two electron domains, as in ethyne $\text{C}_2\text{H}_2$

Molecules of each of the three hybridization demonstrate spatial configurations that would maximizes the separation between the electron domains.

Carbon atoms with a $sp^{3}$ hybridization would demonstrate a tetrahedral configuration with a bond angle of approximately $109.5\textdegree{}$
Carbon atoms with a $sp^{2}$ hybridization would demonstrate a triangular planar configuration with a bond angle of $120\textdegree{}$
Carbon atoms with a $sp$ hybridization would demonstrate a linear configuration with a bond angle of $180\textdegree{}$

Bond angles are characteristic of the spatial configuration of electron domains and identifies the hybridization of the central carbon atom.

Note that each hydrogen atom contains only one valence electron and would form only single bonds. It takes two valence electrons for oxygen atoms to achieve an octet such that each oxygen form only two bonds at a single time. Therefore given the fact that the carbon is bonded to both hydrogen and oxygen, only the following hybridizations are possible

$sp^{3}$ in which the oxygen atom forms a carbon-oxygen double bond with the central carbon atom;
$sp^{2}$ in which the oxygen atom forms a single bond with the central carbon atom and with a second atom.

3 0

3 years ago

What is the Lewis dot structure for oxygen?

BabaBlast [244]

This is the Lewis Dot structure for oxygen

5 0

3 years ago

What is called a measurement and does involve a number and unit in chemistry?​

What is called a measurement and does involve a number and unit in chemistry?