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3 years ago

An atom contains 16 protons, 18 neutrons, and 16 electrons what is its mass number?

Chemistry

1 answer:

Oksanka [162]3 years ago

4 0

protons

neutrons

electrons

Right from the start, you know that you're indeed dealing with a neutral atom, since the number of protons it has in its nucleus is equal to the number of electrons it has surrounding its nucleus.

Now, an atom's atomic number,

, tells you how many protons it has in its nucleus. Nothing more, nothing less.

In your case, you are told that the atom contains

protons in its nucleus, which means that

will be equal to

A quick look in the periodic table will reveal that you're dealing with an atom of sulfur,

An atom's mass number,

, tells you how many protons and neutrons it contains in its nucleus. Since the number of protons is given by

, you can say that

no. of neutrons

In your case, the atom contains

neutrons in its nucleus. This means that

will be equal to

Finally, focus on the atom's electron configuration, which you know that must account for a total of

electrons.

Its noble gas shorthand notation, which uses the electron configuration of neon,

, the noble gas that comes before sulfur in the periodic table, will look like this

[

]

You might be interested in

If the chemical properties of a substance remain unchanged and the appearance or shape of an substance changes it is called a

vladimir1956 [14]

Answer:

Physical change

Explanation:

Physical change -

It is the type of reversible change , where there is change in the state of the matter , is referred to as a physical change .

There is no chemical process involved during state change , i.e. , no new substance is formed .

Hence , from the given statement of the question, the correct term is physical change.

3 0

2 years ago

Describe what happens to particles as they go through a phase change and energy is added

S_A_V [24]

Solid-When a solid is heated the particles gain energy and start to vibrate faster and faster. Initially the structure is gradually weakened which has the effect of expanding the solid. Further heating provides more energy until the particles start to break free of the structure. Although the particles are still loosely connected they are able to move around. At this point the solid is melting to form a liquid.

Liquid-As the liquid gets warmer more particles have sufficient energy to escape from the liquid. Eventually even particles in the middle of the liquid form bubbles of gas in the liquid. At this point the liquid is boiling and turning to gas. The particles in the gas are the same as they were in the liquid they just have more energy. At normal atmospheric pressure all materials have a specific temperature at which boiling occurs. This is called the "boiling point" or boiling temperature.

Description of Phase Change Term for Phase Change Heat Movement During Phase Change

Solid to liquid Melting Heat goes into the solid as it melts.

Liquid to solid Freezing Heat leaves the liquid as it freezes.

Liquid to gas Vaporization, which includes boiling and evaporation. Heat goes into the liquid as it vaporizes.

Gas to liquid Condensation Heat leaves the gas as it condenses.

Solid to gas Sublimation Heat goes into the solid as it sublimates.

3 0

3 years ago

consider the reaction between calcium oxide and carbon dioxide: cao ( s ) + co 2 ( g ) → caco 3 ( s ) a chemist allows 14.4 g of

MakcuM [25]

Answer:

CaO is the limiting reagent

Theoritical yield = 25.71 g

% Yield = 75.44%

Explanation:

1 mole = Molar mass of the substance

Molar Mass of CaO = 56 g/mol

Molar Mass of CaCO3 = 100 g/mol

Molar mass of CO2 = 44 g/mol

The balanced Equation is :

$CaO + CO_{2}\rightarrow CaCO_{3}$

1 mole of CaO reacts with = 1 mole of CO2

56 g of CaO reacts with = 44 g of CO2

1 g of CaO reacts with =

$\frac{44}{56}$

= 0.785 g of CO2

So,

14.4 g of CaO must react with = (14.4 x 0.785) g of CO2

= 11.31 g of CO2

Needed = 11.31 g

Available CO2 = 13.8 g (given)

So CO2 is in excess , hence CaO is the limiting reagent and product will produce from 14.4 g of CaO

$CaO + CO_{2}\rightarrow CaCO_{3}$

1 mole of CaO will produce 1 mole pf CaCO3

56 g of CaO produce = 100 g of CaCO3

1 g of CaO produce =

$\frac{100}{56}$

= 1.785 g of CaCO3

14.4 g of CaO will produce = (1.785 x 14.4) g of CaCO3

= 25.71 g of CaCO3

Theoritical Yield of CaCO3 = 25.71 g

Actual yield = 19.4 g

Percent Yield =

$\frac{Actual\ yield}{Theoritical\ yield}\times 100$

$\frac{19.4}{25.71}\times 100$

= 75.44 %

6 0

3 years ago

Based on the molecular formula, determine whether each of the following is an alkane, alkene, or alkyne. (Assume that the hydroc

stealth61 [152]

Answer:

C₃H₆ is an alkene

C₆H₁₂ is an alkene

C₈H₁₈ is an alkane

C₇H₁₂ is an alkyne

Explanation:

To determine which of the compound is alkane, alkene, or alkyne,we shall use the general formula of alkane, alkene, and alkyne. This is illustrated below:

General formula for alkane => CₙH₂ₙ₊₂

General formula for alkene => CₙH₂ₙ

General formula for alkyne => CₙH₂ₙ₋₂

For C₃H₆:

n = 3

Alkane => CₙH₂ₙ₊₂ => C₃H₂₍₃₎₊₂ => C₃H₈

Alkene => CₙH₂ₙ => C₃H₂₍₃₎ => C₃H₆

Alkyne => CₙH₂ₙ₋₂ => C₃H₂₍₃₎₋₂ => C₃H₄

Thus, C₃H₆ is an alkene

For C₆H₁₂:

n = 6

Alkane => CₙH₂ₙ₊₂ => C₆H₂₍₆₎₊₂ =>C₆H₁₄

Alkene => CₙH₂ₙ => C₆H₂₍₆₎ => C₆H₁₂

Alkyne => CₙH₂ₙ₋₂ => C₆H₂₍₆₎₋₂ => C₆H₁₀

Thus, C₆H₁₂ is an alkene

For C₈H₁₈:

n = 8

Alkane => CₙH₂ₙ₊₂ => C₈H₂₍₈₎₊₂ => C₈H₁₈

Alkene => CₙH₂ₙ => C₈H₂₍₈₎ => C₈H₁₆

Alkyne => CₙH₂ₙ₋₂ => C₈H₂₍₈₎₋₂ => C₈H₁₄

Thus, C₈H₁₈ is an alkane.

For C₇H₁₂:

n = 7

Alkane => CₙH₂ₙ₊₂ => C₇H₂₍₇₎₊₂ => C₇H₁₆

Alkene => CₙH₂ₙ => C₇H₂₍₇₎ => C₇H₁₄

Alkyne => CₙH₂ₙ₋₂ => C₇H₂₍₇₎₋₂ => C₇H₁₂

Thus, C₇H₁₂ is an alkyne.

SUMMARY:

C₃H₆ is an alkene

C₆H₁₂ is an alkene

C₈H₁₈ is an alkane

C₇H₁₂ is an alkyne

3 0

3 years ago

Select all the true statements regarding chemical equilibrium.

svetoff [14.1K]

Answer:

Choice B, C, and D.

Explanation:

Choice A is not true in general. Here's a way to think about that. Consider a very special equilibrium where the concentration of reactants and products are indeed equal. When one of the external factors (such as temperature) changes, the equilibrium will shift towards either side of the reaction. More products will be converted to reactants, or vice versa. Either way, in the new equilibrium, the concentration of the reactants and products will not be equal any more.

Choice B should be considered with choice C and D in mind.

Choice C is indeed correct. The reaction rate would not be zero unless all the reactants were used up or taken out of the system. That's not what happens in an equilibrium. Instead, when reaction rate is plotted against time, the graph for reactions in both directions will eventually flat out at a non-zero value.

Choice D explains why even though choice C is correct, the concentration of a system at equilibrium stays the same. At the equilibrium, reactions in both directions are still happening. However, during the time it takes for the forward reaction use up some reactant particles, the reverse reaction would have produced these particles again. On a large scale, there would be no observable change to the concentration of each species in the equilibrium. Therefore, choice B is also correct.

6 0

3 years ago