b. Which two neutral elements have different numbers of protons but similar properties?

Answers

Answer 1

Answer:

Helium and neon

Explanation:


Related Questions

Prokaryotic is an example of a/an-

A:tissue
B:cell type
C:organ
D:organism

Answers

Answer:

B. Cell Type

Explanation:

that is the answer i believe

Answer:

option b- cell type

Explanation:

almost absolutely positive

A compound is found to contain 26.73 % phosphorus, 12.09 % nitrogen, and 61.18 % chlorine by mass. What is the empirical formula for this compound

Answers

Answer:

[tex]PNCl_2[/tex]

Explanation:

Hello!

In this case, when determining empirical formulas by knowing the by-mass percent, we first must assume the percentages as masses so we can compute the moles of each element:

[tex]n_P=\frac{26.73g}{30.97g/mol}=0.863mol\\\\n_N=\frac{12.09g}{14.01g/mol}=0.863mol\\\\n_C_l=\frac{61.18g}{35.45g/mol}=1.726mol[/tex]

Now, for the determination of the subscript of each element in the empirical formula, we divide the moles by the fewest moles (P or N):

[tex]P=\frac{0.863mol}{0.863mol}=1\\\\N= \frac{0.863mol}{0.863mol}=1\\\\Cl=\frac{1.726mol}{0.863mol}2[/tex]

Thus, the empirical formula is:

[tex]PNCl_2[/tex]

Regards!

A mixture of ethyne gas (C2H2) and methane gas (CH4) occupied a certain volume at a total pressure of 16.8 kPa. When the sample burned, the products were CO2 gas and H2O vapor. The CO2 was collected and its pressure found to be 25.2 kPa in the same volume and at the same temperature as the original mixture. What percentage of the original mixture was methane

Answers

Answer:

50%

Explanation:

Let assume that there are:

"a" moles of CH4 & "b" moles of C2H2

Then by applying the ideal gas equation:

PV = nRT

[tex]16.8 \times 10^3 \times V = (a+b)RT[/tex]

Make (a+b) the subject of the formula:

[tex](a+b) = \dfrac{16800 \ V }{RT} mol[/tex] --- (1)

Since 1 mole of CH₄ yields 1 mol of CO₂ & 1 mol of C₂H₂ yields 2 moles of CO₂

Then;

the total moles of CO₂ = (a +2b)

Now:

[tex]25.3 \times 10^3 \times V = (a+ 2b)RT[/tex]

[tex](a + 2b) = \dfrac{25200 \ V}{RT \ mol}[/tex]    ---- (2)

By solving the above equations

[tex]a = \dfrac{8400 \ V}{RT} \\ \\ b = \dfrac{8400 \ V}{RT}[/tex]

Hence, the estimate of the percentage of methane in the original mixture is:

[tex]= 100 \times \dfrac{a}{(a+b)}[/tex]

[tex]= 100 \times \dfrac{8400\dfrac{ \ V}{RT} }{8400\dfrac{ \ V}{RT} + 8400\dfrac{ \ V}{RT}}[/tex]

= 50%

A 600. mL beaker has an inner diameter of 77.0 mm. What is the vertical distance between the 100. mL marks on the side of the beaker

Answers

Answer:

[tex]h=12.9cm[/tex]

Explanation:

Hello!

In this case, since we can consider the beaker until the 100-mL mark as a cylinder, we can use the following equation to relate its diameter, vertical distance or height and volume:

[tex]V=\pi h\frac{d^2}{4}[/tex]

Thus, since we know the diameter, volume (which is equivalent to 600 cm³) and π, we can plug in to obtain:

[tex]600cm^3=\pi *h*\frac{(77.0mm)^2}{4}[/tex]

It means it is necessary to take the mm to cm and solve for h:

[tex]h=\frac{600cm^3}{\pi*\frac{(7.70cm)^2}{4}} \\\\h=12.9cm[/tex]

Best regards!

The distance between each 100 mL mark is 2.15 cm.

The volume of a cylinder is obtained using the formula;

V = πr^2h

Now, we have the following information;

Volume of the cylinder = 600. mL or 600 cm^3

Diameter of the cylinder = 77 mm or 7.7 cm

Radius of the cylinder = 7.7/2 = 3.85 cm

Height of the cylinder  = h

Hence;

600 = 3.142 × ( 3.85 )^2 × h

h = 600/3.142 × ( 3.85 )^2

h = 12.88 cm

There are six 100 mL marks on the beaker, the distance between each 100 mL mark =  12.88 cm/6 = 2.15 cm

Learn more about volume: https://brainly.com/question/12748872

GIVING OUT BRAINLIEST!!!!!!!!!
Which substance has the lowest specific heat?
O Beach sand
O
Beach water
O Ice
Pool water

Answers


Uhhhh I pretty sure it’s pool water

Which of these factors are biotic? (SELECT ALL THAT APPLY.)
animals
light
minerals
water
plants

Answers

Answer:

plants

Explanation:

because it produces ( i am a third grade student and don't know if it is right or not)

What is one reason a fuse may blow out? NEED HELP NOW

Answers

Answer:

Too high voltage which can't be held by the fuse

Elements in the same group of the periodic table have the same number of

Answers

Answer:

valence electrons

The elements in each group have the same number of electrons in the outer orbital. Those outer electrons are also called valence electrons. They are the electrons involved in chemical bonds with other elements. Every element in the first column (group one) has one electron in its outer shell.

what is fractional distillation what is fractional distillation explain it with the help of an activity ​

Answers

Answer:

Fractional distillation is a method for separating liquids with different boiling points. For example, liquid ethanol can be separated from a mixture of ethanol and water by fractional distillation. ... The boiling point of ethanol is 78°C and the boiling point of water is 100°C.

Please help!!! The person who gets it right gets brainlist

Answers

Answer:B because all of the atoms exploded AND GRAVITY WAS CREATED AND forced molecules together (God caused it btw)

Explanation:The BIBLE

How do we use positive and negative signs to communicate the direction of a vector

Answers

Answer:

Two vectors are equal if they have the same magnitude and the same direction. Just like scalars which can have positive or negative values, vectors can also be positive or negative. A negative vector is a vector which points in the direction opposite to the reference positive direction.

How many electrons will the lithium atom give up to become stable?

a. 1
b. 2
c. 3
d. 4

Answers

Recall that most atoms are stable when their outermost ring has eight electrons. (Some atoms, such as lithium and beryllium, are stable when their outermost ring has two electrons.)

Answer: 2

Explanation: that’s the answer for the quiz

pleaseee help thank youu​

Answers

Answer:

i just took it the answers is C

Explanation:

It’s d hope it’s correct I triedjsjjddjsnsnshsje

25) Organize the following in the most likely order of increasing melting point.
NH3 (polar)
CH4 (nonpolar)
CH10 (nonpolar)
HBr (polar)
A) NH3 < HBr < CH4 < C4H10
B) CH4 < C4H10 < HBr < NH3
NH3 CH4 = HBr < 4H10 < NH3
D)

Answers

Answer:b

Explanation:

Right

Aton Van Leeuwenhoek was the first scientist to discover prokaryotic organisms. These single-celled organisms lack a nucleus and other membrane bound organelles but do have a cell membrane, DNA, and even a cell wall. Choice one of the answer. A. All known living things are made up of one or more cells. B. All living cells come from pre-existing cells by division. C. A cell is the fundamental unit of structure and function in all living organisms. D. No answer text provided

Answers

Answer: a

Explanation:

Why is your body going through physical and chemical changes?

Answers

Answer:

Physical and chemical changes can occur almost everywhere, even in our bodies! Food must be broken down into a form that our cells can use. When we eat, our bodies physically break down food into small pieces. Our bodies also chemically break down those small pieces of food into tiny organic molecules.

Explanation:

If a piece of cadmium with a mass of 37.60 g and a temperature of 100.0 oC is dropped into 25.00 cc of water at 23.0 oC, what will be the final temperature of the system

Answers

Answer:

[tex]T_{eq}=28.9\°C[/tex]

Explanation:

Hello!

In this case, since it is observed that hot cadmium is placed in cold water, we can infer that the heat released due to the cooling of cadmium is gained by the water and therefore we can write:

[tex]Q_{Cd}+Q_{W}=0[/tex]

Thus, we insert mass, specific heat and temperatures to obtain:

[tex]m_{Cd}C_{Cd}(T_{eq}-T_{Cd})+m_{W}C_{W}(T_{eq}-T_{W})=0[/tex]

In such a way, since the specific heat of cadmium and water are respectively 0.232 and 4.184 J/(g °C), we can solve for the equilibrium temperature (the final one) as shown below:

[tex]T_{eq}=\frac{m_{Cd}C_{Cd}T_{Cd}+m_{W}C_{W}T_{W}}{m_{Cd}C_{Cd}+m_{W}C_{W}}[/tex]

Now, we plug in to obtain:

[tex]T_{eq}=\frac{37.60g*0.232\frac{J}{g\°C}*100.00\°C+25.00g*4.184\frac{J}{g\°C}*23.0\°C}{37.60g*0.232\frac{J}{g\°C}+25.00g*4.184\frac{J}{g\°C}}\\\\T_{eq}=28.9\°C[/tex]

NOTE: since the density of water is 1g/cc, we infer that 25.00 cc equals 25.00 g.

Best regards!

QUESTION 3 What mass (in g) of glucose, C6H1206, must be added to 300.7 g of water to prepare a 0.322 molal solution? Enter your answer with 3 significant figures and no units.

Answers

Answer:

17.42 g of glucose, C₆H₁₂O₆

Explanation:

From the question given above, the following data were obtained:

Mass of water = 300.7 g

Molar solution = 0.322 M

Mass of glucose =.?

Next, we shall convert 300.7 g to L. This can be obtained as follow:

1000 g = 1 L

Therefore,

300.7 g = 300.7 g × 1 L / 1000 g

300.7 g = 0.3007 L

Next, we shall determine the number of mole of glucose in the molar solution. This can be obtained as follow:

Volume of solution = 0.3007 L

Molar solution = 0.322 M

Mole of glucose =?

Molar solution = mole / Volume

0.322 = mole of glucose / 0.3007

Cross multiply

Mole of glucose = 0.322 × 0.3007

Mole of glucose = 0.0968 mole

Finally, we shall determine the mass of glucose, C₆H₁₂O₆, needed to produce prepare the solution. This can be obtained as follow:

Mole of C₆H₁₂O₆ = 0.0968 mole

Molar mass of C₆H₁₂O₆ = (12×6) + (1×12) + (16×6)

= 72 + 12 + 96

= 180 g/mol

Mass of C₆H₁₂O₆ =?

Mole = mass /Molar mass

0.0968 = Mass of C₆H₁₂O₆ / 180

Cross multiply

Mass of C₆H₁₂O₆ = 0.0968 × 180

Mass of C₆H₁₂O₆ = 17.42 g

Thus, 17.42 g of glucose, C₆H₁₂O₆ is needed to prepare the molar solution.

As ice cream freezes do the chemical properties of the substance change? Explain why or why not?

Answers

Yes. When ice cream is melted is a liquid and therefore jot a solid. When it freezes it becomes a solid


How many atoms are in .938 moles of CO2?

Answers

Answer: 1.695x10^24 atoms

Explanation: 0.938 moles CO2 = 0.938xavogadro number molecules CO2, so number of atoms = 3x0.938x6.02214076x10^23 = 1.695x10^24

Which of the following is NOT an advantage of a wireless network? convenience reliability security speed

Answers

Answer:

Security

Explanation:

A wireless network consists of good connection with fast speed, convenience, and reliability. Security is a major problem with wireless connection as someone can get your information by joining the same connection as you.

What are the outcomes of the ice cap melting? Choose all that apply.


1. Light cannot be reflected back to the atmosphere


2. Sea level rises


3. Absorption of solar radiation leads to increase in ocean temperature


4. Ocean remains unaffected

Answers

Answer:

2. sea level rises sorry if it's wrong

PLEASE HELP WILL MARK BRAINLIEST
how does the container with the plastic wrap stimulate carbon dioxide in the atmosphere?

Answers

Answer:

The Earth’s greenhouse effect is a natural consequence of the chemical makeup of its atmosphere. If it

were not for the greenhouse effect, life as we know it could not exist on Earth: it would be too cold. Our

atmosphere is made mostly of nitrogen and oxygen, but also contains several other gases. These include

carbon dioxide, methane, nitrous oxide, water vapor and ozone, which are known as greenhouse gases.

Greenhouse gases are released naturally through geologic processes and the metabolic activity of living

things. However, there is an ongoing debate over human effects on Earth’s global climate. Human industrial activity on the planet has increased the quantities of greenhouse gases through agriculture, manufacturing, power generation, and engines used for transportation. Key questions include: Is the average temperature of Earth increasing? Does the presence of human beings contribute to global warming? If the temperature of Earth does become warmer, how will it affect us?

Explanation:

QUESTION 3
Identify the number that has 3 significant figures.
O A. 100
OB. 12.0
O C. 120
OD. 123.00

Answers

Answer:

D

Explanation:

Which equation could be used to solve for the average speed of a car that travels 90m in 20 seconds?​

Answers

Answer:

Vav=d/t

Explanation:

Because the question already gave d=90m and t=20s. Because the car is the thing that can not travel the same distances at the same times.So the equation is V[tex]\\_{av}[/tex]=[tex]\frac{d}{t} \\[/tex]

What element contains 8 valence electrons and tends not to react with other elements?

Answers

Answer:

C. Oxygen

Explanation:

Oxygen has 8 electrons and doesn't react with fluorine noble gases

The concentration of hydrogen peroxide solution can be determined by
titration with acidified potassium manganate(VII) solution. In this reaction
hydrogen peroxide is oxidised to oxygen gas. A 5.0 cm sample of hydrogen
peroxide solution was added to a volumetric flask and made to 250 cm
of the aqueous solution. A 25.0 cm sample of this solution was acidified
and reacted completely with 24 35 em of 0.0187 mol dm potassium
manganate(VII) solution
(ay Write a balanced equation for the reaction between acidified KMnO
solution and H.O.
(b) Calculate the concentration of the original H,O, solution in mol dm​

Answers

The question is incomplete, the complete reaction equation is;

The concentration of a hydrogen peroxide solution can be determined by titration

with acidified potassium manganate(VII) solution. In this reaction the hydrogen

peroxide is oxidised to oxygen gas.

A 5.00 cm3 sample of the hydrogen peroxide solution was added to a volumetric flask

and made up to 250 cm3 of aqueous solution. A 25.0 cm3 sample of this diluted

solution was acidified and reacted completely with 24.35 cm3 of 0.0187 mol dm–3

potassium manganate(VII) solution.

Write an equation for the reaction between acidified potassium manganate(VII)

solution and hydrogen peroxide.

Use this equation and the results given to calculate a value for the concentration,

in mol dm–3, of the original hydrogen peroxide solution.

(If you have been unable to write an equation for this reaction you may assume that

3 mol of KMnO4 react with 7 mol of H2O2. This is not the correct reacting ratio.)

Answer:

2.275 M

Explanation:

The equation of the reaction is;

2 MnO4^-(aq) + 16 H^+(aq) + 5H2O2(aq) -------> 2Mn^+(aq) + 10H^+ (aq) + 8H2O(l)

Let;

CA= concentration of MnO4^- =  0.0187 mol dm–3

CB = concentration of H2O2 = ?

VA = volume of MnO4^- = 24.35 cm3

VB = volume of H2O2 = 25.0 cm3

NA = number of moles of  MnO4^- = 2

NB = number of moles of H2O2 = 5

From;

CAVA/CBVB = NA/NB

CAVANB = CBVBNA

CB = CAVANB/VBNA

CB = 0.0187 * 24.35 * 5/25.0 * 2

CB = 0.0455 M

Since  

C1V1 = C2V2

C1 = initial concentration of H2O2 solution = ?

V1 = initial volume of H2O2 solution =  5.0 cm3

C2 = final concentration of H2O2 solution= 0.0455 M

V2 = final volume of H2O2 solution = 250 cm3

C1 = C2V2/V1

C1 = 0.0455 * 250/5

C1 = 2.275 M

Use the following reaction:

CuCl2 + 2 NaNO3 → Cu(NO3)2 + 2 NaCl

If 90.0 grams of copper (II) chloride react with 120.0 grams of sodium nitrate, how much sodium chloride can be formed (in grams)?

Answers

Answer:

78.4g

Explanation:

Given parameters:

Mass of copper (II) chloride  = 90g

Mass of sodium nitrate  = 120g

Unknown:

Mass of sodium chloride that can be formed  = ?

Solution:

The balanced chemical reaction is:

            CuCl₂   +   2NaNO₃ →   Cu(NO₃)₂   +   2NaCl

Let us find the limiting reactant. This reactant will determine the extent of the reaction of the amount of product that will be formed.

First, convert the masses to number of moles;

      Number of moles  = [tex]\frac{mass}{molar mass}[/tex]

Molar mass of   CuCl₂  = 63.5 + 2(35.5) = 134.5g/mol

Molar mass of NaNO₃   = 23 + 14 + 3(16) = 85g/mol

  Number of moles of CuCl₂ = [tex]\frac{90}{134.5}[/tex]  = 0.67mole

  Number of moles of NaNO₃  = [tex]\frac{120}{85}[/tex]  = 1.41mole

From the balanced reaction equation:

      1 mole of CuCl₂   would react with 2 moles of NaNO₃

     0.67mole of CuCl₂   would require   0.67 x 2  = 1.34mole of NaNO₃

So, CuCl₂ is the limiting reactant

     1 mole of CuCl₂ will produce 2 mole of NaCl

    0.67mole of CuCl₂ will therefore yield 0.67 x 2 = 1.34mole of NaCl

Mass of NaCl = number of moles x molar mass

  Molar mass of NaCl = 23 + 35.5 = 58.5g/mol

 

Mass of NaCl  = 58.5 x 1.34  = 78.4g

Mg(s)+2HCl(aq)  →  MgCl2(aq)+H2(g)

In an experiment, a student places a small piece of pure Mg(s) into a beaker containing 250.mL of 6.44MHCl(aq) . A reaction occurs, as represented by the equation above.


(a) Write the balanced net ionic equation for the reaction between Mg(s) and HCl(aq) .

Answers

Answer:

[tex]Mg(s)+2H^+(aq)\rightarrow Mg^{2+}(aq)+H_2(g)[/tex]

Explanation:

Hello!

In this case, since the writing of a net ionic equation first implies writing the complete molecular equation:

[tex]Mg(s)+2HCl(aq) \rightarrow MgCl_2(aq)+H_2(g)[/tex]

We can see that HCl and MgCl2 are ionized because they are aqueous, thus we write:

[tex]Mg(s)+2H^+(aq)+2Cl^-(aq) \rightarrow Mg^{2+}(aq)+2Cl^-(aq)+H_2(g)[/tex]

In such a way, we can cancel out the chloride ions as they are the spectator ones to obtain the net ionic one:

[tex]Mg(s)+2H^+(aq)\rightarrow Mg^{2+}(aq)+H_2(g)[/tex]

Best regards!

___C3H8 + ___O2 --> ___H2O + ___CO2

Answers

Answer:

C3H8 + 5O2 ‐‐‐‐‐‐‐‐> 4H2O + 3CO2

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Here's the photo=0.2 0.3 Which list accurately identifies the hierarchy of space from largest to smallestO aObOcOdSolar system, galaxy, planet, universeGalaxy, solar system, planet, moonGalaxy, solar system, universe, moonSolar system, universe, galaxy, moon sidjeosidncjskskd HELP Which of the following is a type of business communication?A. A business letterB. A memoC. An e-mailD. All of the above which of the following is not a social need of a school age childA) playing with other childrenB) establishing clear boundariesC) Reading dailyD) encouraging involvement in clubs or organizations PLZZZ HELPPPOver a one week period in the summer, the price of a gallon of gas increased from $2.35 to $2.82. By what percent did the price of gas increase over that week? A. 10% B. 20% C. 30% D. 40% I uhhhhh please help How do i multiply 13.02 x 5 PLEASE HELP ASAP WILL GIVE BRAINLIEST What is the value of x?Enter your answer in the box.x = Which belongs in each place Tell whether the angles are complementary or supplementary. Then find the value of a2x(3x + 25) Would newspapers be likely to write articles about a rebellion in anearby country? Why or why not? WILL MARK BRAINLIEST!!! which of the following is a pair of complementary angles What is the main idea of the coronavirus how did people change their life name of 70 countries which conduct transparency International 9 The friction between the car and the mud is equivalent to the__________________.(a) Resultant force(b) Drag force (c) Equivalent force(d) Stretch force(e) None Which of the following correctly shows clustering for the problem 72 x 13?72 x 10 + 72 x 372 x 12 + 72 x 170 x 10 + 2 x 372 x 10 + 72 x 13 3. What type of bond holds the backbone together?A. CovalentB. HydrogenC. lonic Peaches are on sale at $0.95 per pound. Mrs. Hinkle bought 3.45 pounds of peaches. How much did she pay for the peaches?