1. What does the atomic number of an element represent? What does the mass number of an
atom represent?

Answers

Answer 1
The atomic number represents or stand for the distinction identity of a chemical element. It is usually defined as the number of protons present number in an atom of an element, which is also equal to the number of electrons

Related Questions

7.08 moles of ammonia (NH3) is formed in the following reaction. How many grams of
hydrogen reacted?
3H2 + N2 + 2NH3

Answers

Answer:

Mass = 21.24 g

Explanation:

Given data:

Number of moles of ammonia = 7.08 mol

Mass of hydrogen reacted = ?

Solution:

Chemical equation:

3H₂ + N₂      →    2NH₃

Now we will compare the moles of ammonia and hydrogen.

             NH₃        :         H₂  

              2           :         3

          7.08         :        3/2×7.08 = 10.62

Mass of hydrogen:

Mass = number of moles × molar mass

Mass = 10.62 mol × 2 g/mol

Mass = 21.24 g

Which element easily gains one electron to form a negative ion?

Flourine

Magnesium

Nitrogen

Lithium

Answers

Answer: Fluorine

Explanation: Fluorine has an oxidation state of -1, meaning it gains 1 electron in chemical bonds, forming a negative ion. Magnesium has an oxidation state of +2, nitrogen has -3, and lithium has an oxidation state of +1.

Answer:

Fluorine.

Explanation:

I took this test not to long ago. I got this question correct. Also, the reason is because every other element is balanced.

16.
Mg(OH)2 +
H.PO.-> ||||Mg(PO2 +
H2O
2,3,6,1
3, 3, 1,6
3, 2, 1,6
2,3,1,3

17. Cr+Fe(NO.)2 ->
Fe +_ Cr(NO3)2
4,6,6,2
0 2,3,2,3
0 1,3,3,1
02.3, 1.2
0 2,3,3,2

these are two questions separated but I would REALLY appreciate if someone could do them it’s for a test

Answers

Answer:

3,2,1,6

2,3,3,2

Explanation:

HOPE THIS HELPED

Calculate the molar mass of each salt.

Element Molar mass (g/mol)
Beryllium (Be) 9.012
Magnesium (Mg) 24.31
Cobalt (Co) 58.93
Cadmium (Cd) 112.41
Iodine (II) 126.90

a. The Molar mass of CaBr2 is:_______
b. The Molar mass of BeBr2 is:_______
c. The Molar mass of CdBr2 is:_______
d. The Molar mass of CuBr2 is:_______

Answers

Answer:

a.

[tex]M_{CaBr_2}=40.08+79.9*2=199.88 g/mol[/tex]

b.

[tex]M_{BeBr_2}=9.012+79.9*2=168.81g/mol[/tex]

c.

[tex]M_{CdBr_2}=112.41+79.9*2=272.21g/mol[/tex]

d.

[tex]M_{CuBr_2}=63.55+79.9*2=223.35g/mol[/tex]

Explanation:

Hello!

In this case, since the molar mass of a compound is computed by adding the molar mass of each element composing it and multiplying it by the number of atoms in the molecule, we have:

a.

[tex]M_{CaBr_2}=40.08+79.9*2=199.88 g/mol[/tex]

b.

[tex]M_{BeBr_2}=9.012+79.9*2=168.81g/mol[/tex]

c.

[tex]M_{CdBr_2}=112.41+79.9*2=272.21g/mol[/tex]

d.

[tex]M_{CuBr_2}=63.55+79.9*2=223.35g/mol[/tex]

Best regards!

Why do the balls of the Newton’s cradle eventually stop?

Answers

The balls of the Newton’s cradle eventually stop because they loose energy as they collide.

The balls of the Newton’s cradle lose energy to the air as they move through it due to friction.

These balls make sound when they collide, and consequently the balls loose energy to heat upon collision.

The balls loose energy as they collide with each other and eventually stop.

Thus, we can conclude that the balls of the Newton’s cradle eventually stop because they loose energy as they collide.

Learn more about Newton’s cradle here: https://brainly.com/question/14063949

How much force does a 35 kg child have that is running through the house at an acceleration of 20 m/s2?

Answers

Answer:

700N

Explanation:

F=ma

mass=35

acceleration =20

Can ya help me out real quick?

18) Choose the best answer.

Calculate the amount of heat required. You will need to use your Periodic Table and Table B-3 below.

table - Specific Heat of Selected Substances

How much heat is released by lowering the temperature of 825 grams of molten (liquid) lead at 800K to solid lead at 295K? Lead melts at 600.61K.

-94.54kJ
-8873kJ
302kJ
-204kJ
209kJ

Answers

Answer:

302 kj heat is released by lowering the temperature

302kJ is the amount of heat which is released by lowering the temperature of 825 grams of molten (liquid) lead at 800K to solid lead at 295K. Therefore, the correct option is option C.

What is heat?

Heat is energy that is transmitted from one object to another as a result of a temperature differential. When two bodies of differing temperatures come into contact, energy is transmitted as heat flows first from hotter to the colder.

melting point of lead= 328°C.

T₁ = 328 + 273 = 800K

T₂ = 295K

T₃ = 600.61K

latent head of fusion of lead = 4.8 kJ/mol

specific heat of solid lead= 0.13 J/g/K

specific heat of liquid lead = 0.14 J/g/K

heat= mS∆T + (m/M)Lf + mS∆T'

= 23g × 0.13 J/g/K × (601 - 297)K + 23g/207g/mol × 4.8 kJ/mol + 23g × 0.14 J/g/K × (702 - 601)K

=302kJ

Therefore, the correct option is option C.

To learn more about heat, here:

https://brainly.com/question/13411214

#SPJ2

3) 46.7 L of a gas is initially at a pressure of 662 torr and a temperature of 266 K. If the volume decreases to 35.0 L and the temperature increases to 342 K, what is the new pressure?​

Answers

Answer:

The new pressure is 1,135.67 torr

Explanation:

Boyle's law establishes the relationship between pressure and volume of a gas when the temperature is constant, establishing that the pressure of a gas in a closed container is inversely proportional to the volume of the container. Mathematically, this law says that the product of pressure and volume is constant:

P*V=k

Charles's law establishes the relationship between the temperature and the volume of a gas when the pressure is constant. This law states that the volume is directly proportional to the temperature of the gas. So, Charles's law says that the quotient that exists between the volume and the temperature will always have the same value:

[tex]\frac{V}{T} =k[/tex]

Finally, Gay-Lussac's Law is a gas law that relates pressure and temperature at constant volume. This law says that the pressure of the gas is directly proportional to its temperature:

[tex]\frac{P}{T} =k[/tex]

Combined law equation is the combination of three gas laws called Boyle's, Charlie's and Gay-Lusac's law:

[tex]\frac{P*V}{T} =k[/tex]

Analyzing an initial state 1 and a final state 2, it is satisfied:

[tex]\frac{P1*V1}{T1} =\frac{P2*V2}{T2}[/tex]

In this case:

P1= 662 torrV1= 46.7 LT1= 266 KP2= ?V2= 35 LT2= 342 K

Replacing:

[tex]\frac{662 torr*46.7 L}{266 K} =\frac{P2*35 L}{342 K}[/tex]

Solving:

[tex]P2=\frac{342 K}{35 L} *\frac{662 torr*46.7 L}{266 K}[/tex]

P2= 1,135.67 torr

The new pressure is 1,135.67 torr

Terri wants to learn about areas that could be volcanically active. Ernesto wants to learn about the history of rocks in
an area. Which statement is true?
O Terri should use a topographic map and Ernesto should use a geographic map.
O Terri should use a geographic map and Ernesto should use a topographic map.
Terri and Ernesto should both use geographic maps.
Terri and Ernesto should both use topographic maps.

Answers

Terri and Ernesto should both use geographic maps.

may i have brainliest? :D

Answer:

C.

Explanation:

I dunno. took the test and got it right.

In the first 21.0 s of this reaction, the concentration of HBr dropped from 0.550 M to 0.506 M . Calculate the average rate of the reaction in this time interval.

Answers

Answer:

1.048x10⁻³M/s is the rate of reaction

Explanation:

Based on the reaction:

2HBr → H₂ + Br₂

The rate of reaction is defined as:

1/2 Δ[HBr] / Δt

1/2 because the reaction is consuming 2 times HBr per mole of reaction

Where Δ[HBr] is 0.550M - 0.506M = 0.044M

And Δt is 21.0s. The average rate of reaction is:

1/2 0.044M / 21.0s =

1.048x10⁻³M/s is the rate of reaction

What is the number of electrons in an atom that
has 3 protons and 4 neutrons?
(1) 1
(3) 3
(2) 7
(4) 4

Answers

Answer:

(2)

Explanation:

Answer:

7 is answer.

Explanation:

therefore, the mass number of an atom with 3 protons,4 neutrons,and 3 electrons is 7.

I hope it's helpful!

importance of solution in industry? ​

Answers

Answer:The majority of chemical processes are reactions that occur in solution. Important industrial processes often utilize solution chemistry. "Life" is the sum of a series of complex processes occurring in solution. Air, tap water, tincture of iodine, beverages, and household ammonia are common examples of solutions.

A solution is a homogenous mixture of substances with variable composition. The substance present in the major proportion is called the solvent, whereas the substance present in the minor proportion is called the solute. It is possible to have solutions composed of several solutes. The process of a solute dissolving in a solute is called dissolution.

Explanation:

Which group of elements satisfies the octet rule?
Alkali metals
Alkaline earth metals
halogens
Noble gases

Answers

Answer:

the anser is c

Explanation:

a glass of organge juice contains .85dl of juice. how many millimeters of orange juice is that

Answers

Answer:

85 ml

Explanation:

move the decimal place over two times

How many chloride ions are needed to create a neutral compound with a barium ion? A. 2
B. 3
C. 4
D. 1

Answers

Answer:

Barium chloride is represented as BaCl2.

Explanation:

so answer is a.)2

I hope it's helpful!

Letter.A thats the answer

A cube of tin that is 112 mm on each side has a mass of 8.21 grams. A single tin atom has a mass of 118.7 amu. How many tin atoms are in the cube? Report your answer in scientific notation with 3 sig figs. Use e for scientific notation, for example 100. would be written as 1.00e+2

Answers

Answer:

4.17e+22 atoms of tin are present in the cube

Explanation:

We don't require the size of the cube. With the mass and the molar mass of tin = 118.7 amu we can find moles of Tin. As 1 mol = 6.022x10²³ atoms we can find the number of atoms:

Moles Tin:

8.21g * (1mol / 118.7g) = 0.0692 moles Tin

Atoms Tin:

0.0692 moles Tin * (6.022x10²³ atoms / mol) =

4.17e+22 atoms of tin are present in the cube

The number of atoms or molecules in a mole is known as the __________ constant.

Answers

Answer: Avogrado's Constant

Explanation:

One mole of a substance is equal to 6.022 × 10²³ units of that substance (such as atoms, molecules, or ions). The number 6.022 × 10²³ is known as Avogadro's number or Avogadro's constant. The concept of the mole can be used to convert between mass and number of particles.

a. A container has a volume of 20 m3 and initially it contains 25 kg of methane at a pressure of 10 bar. Determine the specific volume in m3/kg. b. Add 5 kg of Ethane to the tank. What is the specific volume of the mixture in m3/kg

Answers

Answer:

a. 0.80 m³/kg

b. 0.67 m³/kg

Explanation:

a.

Step 1: Given data

Volume of the container (V): 20 m³

Mass of methane (m): 25 kg

Step 2: Calculate the specific volume (v) of methane

Specific volume is defined as the number of cubic meters occupied by one kilogram of matter.

v = V/m

v = 20 m³/25 kg = 0.80 m³/kg

b.

Step 1: Calculate the mass of the mixture

m = m(methane) + m(ethane)

m = 25 kg + 5 kg = 30 kg

Step 2: Calculate the specific volume (v) of the mixture

v = V/m

v = 20 m³/30 kg = 0.67 m³/kg

8. A moving truck is loading heavy furniture using a long ramp. Why does this simple machine make the work easier?
The ramp makes the furniture weigh less.
It takes less force to move the furniture up the long ramp.
The ramp acts like a lever to make the work easier.
The furniture fits on the ramp.

Answers

Hey it’s a great night for me so when I thought what u did was why I wanted to 2013 I cry to mitski

PLS HELP ASAP THIS IS DUE IN 10 MINUTES I NEED NUMBER 3, 4 AND 5!

Answers

Answer:

1. B

2. A

3. E

4. D

5. C

Explanation:

In the bloodstream, the effective pKa for carbonic acid is 6.35. If the pH of the blood is 7.40, what percentage of the blood buffer is present as bicarbonate

Answers

Answer:

The 91.8% is present as bicarbonate ion

Explanation:

It is possible to find pH of a buffer using H-H equation:

pH = pKa + log [A⁻] / [HA]

Where pH is 7.40; pKa is 6.36, [A⁻] is concentration of bicarbonate ion and [HA] concentration of carbonic acid

7.40 = 6.35 + log [A⁻] / [HA]

1.05 = log [A⁻] / [HA]

11.22 = [A⁻] / [HA] (1)

As the question is in therms of percentage:

[A⁻] + [HA] = 100 (2)

Replacing (2) in (1):

11.22 = [A⁻] / 100 - [A⁻]

1122 - 11.22[A⁻] = [A⁻]

1122 = 12.22[A⁻]

91,8% = [A⁻]

The 91.8% is present as bicarbonate ion

How many electrons can the n = 4 shell hold?

Answers

Answer: I think its 32 I'm not sure

Explanation:

I’m pretty sure is 34 or it’s either 24

A typical person has an average heart rate of 69.0 beats/min. Calculate the given questions. How many beats does she have in 7.0 years? How many beats in 7.00 years? And finally, how many beats in 7.000 years? Pay close attention to significant figures in this question.

Answers

Answer:

See explanation

Explanation:

Average heart beat = Number of heart beats/ time

7.0 years = 7.0 * 365 * 24 * 60 = 3679200 minutes

If there are 69 beats in 1 minutes

There are x beats in 3679200 minutes

x = 253865 beats

x = 254000.00 beats ( to 3 sf)

beats in 7.00 years = 254000.000 beats

beats in 7.000 years = 254000.0000 beats

what is smaller than atoms and bigger than molecule

Answers

Atoms are smaller than molecules, and they are also the smallest building blocks of matter. Atoms make up molecules when two or more atoms bond.

What is the solid product formed from the reaction between aqueous potassium hydroxide and aqueous iron
(III) chloride?

Answers

Answer:

potassium chloride (KCl)

Explanation:

The reaction between aqueous potassium hydroxide and aqueous iron (III) hydroxide is a double replacement reaction.

3 KOH + FeCl₃ → 3 KCl + Fe(OH)₃

Hope that helps.

Answer:

The correct answer is

[tex]Fe(OH)_{3}[/tex]

Explanation: I tried the KCI and it was incorrect but it showed the answer so here you go!

A person lifts a 10 N box 1 m off the ground in 1 s. How much power does she use? P = W/t
A. 100 W
B. 20 W
O C. 10 w
O D. 12 W

Answers

Answer:

C. 10 W.

Explanation:

Hello!

In this case, since the power the person uses to lift the 10-N load is computed by using the formula:

[tex]P=\frac{W}{t}[/tex]

Whereas W is the work and t the time; we can compute the work by multiplying the force applied in 1 m:

[tex]W=10N*1m=10J[/tex]

Now, we divide it by the time to obtain:

[tex]P=\frac{10J}{1s}=10W[/tex]

Since joules over seconds are watts.

Best regards!

4. What is the specific heat of copper if it took
57.8 J of heat energy added to 10 grams to
produce a 15°C temperature change?

Answers

Answer:

Specific heat capacity of copper is 0.385 J/g.°C

Explanation:

Given data:

Specific heat capacity of copper = ?

Heat absorbed by copper = 57.8 J

Mass of copper = 10 g

Temperature changes = 15°C

Solution:

Formula:

Q = m.c. ΔT

Q = amount of heat absorbed or released

m = mass of given substance

c = specific heat capacity of substance

ΔT = change in temperature

by putting values

57.8 J = 10 g × c × 15°C

57.8 J = 150 g.°C × c

c = 57.8 J / 150 g.°C

c = 0.385 J/g.°C

Specific heat capacity:

It is the amount of heat required to raise the temperature of one gram of substance by one degree.

Specific heat capacity of copper is 0.385 J/g.°C.

How many grams are in 4.63 x 1024

molecules of CCl4?

Answers

Answer:

[tex]m=1,182.8g[/tex]

Explanation:

Hello!

In this case, since the relationship between molecules and mass is first analyzed via the Avogadro's number to compute the moles in the given molecules:

[tex]mol=4.63x10^{24}molec*\frac{1mol}{6.022x10^{23}molec}=7.69mol[/tex]

We now use the molar mass of carbon tetrachloride (153.81 g/mol) to obtain the required grams:

[tex]m=7.69mol*\frac{153.81g}{1mol} \\\\m=1,182.8g[/tex]

Best regards!

The ideal bond angles marked 1, 2, and 3 in the molecule below are about _______, ______, and ______.

Answers

Answer:

D= 109.5 degrees, 109.5 degrees, 120 degrees

Explanation:

The bond angle observed for any bond between two chemical species depends on the hybridization of the atoms.

However, for organic compounds, single bonds normally involve sp3 hybridized atoms with a bond angle of 109.5 degrees such as in the positions marked a and b.

However, a double bond is made of atoms in sp2 hybridized state with a bond angle of 120 degrees such as in c.

A single gold atom has a mass of 197.0 amu. How many gold atoms are in a cube of gold that is 10.0 mm on each side (about the size of a sugar cube) if the density of gold is 19.3 g/cm3

Answers

Answer:

5.90x10²² atoms of gold are present in the cube

Explanation:

First, we must find the volume of the cube in cm³. With density we can find the mass of the gold and the moles using its molar mass. As 1 mol = 6.022x10²³ atoms we can find the number of atoms:

Volume in cm³:

(10.0mm)³ = 1000mm³

1mm³ = 0.001cm³

1000mm³ * (0.001cm³ / 1mm³) = 1cm³

Mass gold:

1cm³ * (19.3g/cm³) = 19.3g Gold

Moles Gold:

19.3g * (1mol / 197.0g) = 0.0980 moles Gold

Atoms gold:

0.0980 moles Gold * (6.022x10²³ atoms / mol) =

5.90x10²² atoms of gold are present in the cube
Other Questions
Definition of dispersal The dollar-euro exchange rate is $1.25 = 1.00 and the dollar-yen exchange rate is 100 = $1.00. What is the euro-yen cross rate? Group of answer choices 1.00 = 0.80 125 = 1.00 None of the above 1.00 = 125 1.)What is an interesting fact about wildlife biologists?2.)What degree do you need as a wildlife biologists?3.) What do you do as a wildlife biologist? Roberto is having his house painted. The job takes three days, and he pays the painter the same hourly rateevery day. The cost of the job is in the chart below.Day 1Day 2 Day 3Hours worked546Amount paid$300$240$360What is the painter's unit rate of change of dollars with respect to time; that is, how much is the painter paid forone hour worked?The unit rate of change isdollars per hour.Graph the proportional relationship described above, with the x-coordinate representing hours worked, andthe y-coordinate representing amount paid in dollars.ySO- Drawing from the following Scatter Chart and the sample sentences and narratives you have worked with in this module, stringtogether your own story. Review as needed for a few minutes, and when you are ready, record your performarve. Penember, whenyou give your performance with enthusiasm and expression, your performance will be better, and you will better remember thebuilding blocks and plot tums you create. To review your performance, select REPLAY. Your story should be about one minute, The climate type that is characterized by hot temperatures and changing precipitation patterns due to monsoons is known as the ____ climate. A humid subtropicalB. tropical wet and dryC tropical wetD highlands While pushing a wagon around the park steve applies a force of 100n along thd handlr which makes 32cangle with the ground if he pushes it 25 metree how much wrk dods he fo please help, i literally have no idea what this means Ms. Santo's patio is in the shape of a trapezoid. The trapezoid and its dimensions are shown below.What is the area of the patio?O 252 square feetO 360 square feetO 315 square feetO144 square feet A quantitative review of the health record for missing reports and signatures that occurs when the patient is in the hospital is referred to as a review pls help do in 30 mins Which of thw following energy sources is in no way derived from the sun Intellectual wellness is a concern for only exceptionally smart people.TrueFalse At a store, notebooks are on sale for 78% off the regular price. The cost of a notebook is represented by n. Which of thefollowing expressions does NOT represent the sale price of the notebooks?O A n +0.22OB. 0.22nOC. n - 0.78nOD. (1 -0.78) Jace receives a shipment of 700oranges. He randomly selects 25oranges to weigh. In that sample, 2oranges weigh 5 ounces. How manyoranges in the shipment can Jacepredict weigh 5 ounces?A. 14B. 644C. 56D. 698 On January 1, 2021, an investor paid $294,000 for bonds with a face amount of $314,000. The contract rate of interest is 11% while the current market rate of interest is 14%. Using the effective interest method, how much interest income is recognized by the investor in 2022 (assume annual interest payments and amortization) -3(n+9)=15i need the step of solving this plzz brainliest if right!! 1(x-2)= -5.5 solving for x. What's the answer Select the interval where g(x) < 0 PLEASE HELP I HAVE 26 MINUTES TO COMPLETE THIS