1
The table gives the composition of three particles
particle
number of
protons
number of
electrons
number of
neutrons
А
15
16
B
15
16
с
15
17
(a) What is the evidence in the table for each of the following?
(i) Particle A is an atom.
(ii) A, B and C are all particles of the same element​

Answers

Answer 1

Answer:

the answer is wurkey churkey since the birdy is really really cute

Explanation:

if the birdy was not squishy then it would have died already?!?!?


Related Questions

why does the sky appear orang or red at sunset and sunrise?

Answers

Answer:

Because the sun is low on the horizon, sunlight passes through more air at sunset and sunrise than during the day, when the sun is higher in the sky. More atmosphere means more molecules to scatter the violet and blue light away from your eyes.

give a reason why it is not advisable to heat magnesium before heating ammonium nitrate​

Answers

Answer:

it can result in an increasing risk of the accumulation of decomposition products, self-heating (from the heat released by the slow decomposition reactions)

Magnesium can result in an increased risk of the accumulation of decomposition products, self-heating (from the heat released by the slow decomposition reactions)

What is ammonium nitrate​?

Ammonium nitrate is used commonly in fertilizers; in pyrotechniques, herbicides, and insecticides; and in the manufacture of nitrous oxide.

When ammonium nitrate is heated, it decomposes exothermically into nitrous oxide and water.

Hence, Magnesium can result in an increased risk of the accumulation of decomposition products, self-heating (from the heat released by the slow decomposition reactions)

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What is the pH of 4.3x10^-7 M solution of H2CO3?

A.)7

B.)4.3

C.)6.4

D.)7.6

ASAP PLS

Answers

Answer:

pH = -log[H⁺] = -log(4.75 x 10⁻⁷) = -(- 6.32 ) = 6.32

Explanation:

Given 4.3 x 10⁻⁷M H₂CO₃ (Ka1 = 4.2 x 10⁻⁷ &  Ka2 = 4.8 x 10⁻¹¹)

Note: The Ka2 value for the 2nd ionization step is so small (Ka2 = 4.8 x 10⁻¹¹) It will be assumed all of the hydronium ions (H⁺) come from the 1st ionization step.  

1st Ionization step

                    H₂CO₃        ⇄   H⁺ + HCO₃⁻

C(initial)     4.3 x 10⁻⁷             0         0

ΔC                   -x                  +x        +x

C(final)      4.3 x 10⁻⁷ - x         x          x

Note: the 'x' value in this analysis can not be dropped as the Conc/Ka value is less than 10². In this case he C/Ka ratio* (4.3E-7/4.2E-7 ≈ 1)  is far below 10².

So, one sets up the equilibrium equation to be quadric and the x-value can be determined.

Ka1 = [H⁺][HSO⁻]/[H₂SO₃] = (x)(x)/(4.3 x 10⁻ - x) = x²/(4.3 x 10⁻⁷ - x) = 4.2 x 10⁻⁷

=>   x² = 4.2 x 10⁻⁷(4.3 x 10⁻⁷ - x)

=>   x² + 4.2 x 10⁻⁷x - 1.8 x 10⁻¹³ = 0              

      a = 1, b = 4.2 x 10⁻⁷, c = - 1.8 x 10⁻¹³

x = b² ± SqrRt(b² - 4(1)(-1.8 x 10⁻¹³ / 2(1) =  4.75 x 10⁻⁷

x = [H⁺] = 4.75 x 10⁻⁷

pH = -log[H⁺] = -log(4.75 x 10⁻⁷) = -(- 6.4 ) = 6.4

______________________

* The Concentration/Ka-value is the simplification test for quadratic equations used in Equilibrium studies. If the C/Ka > 100 then one can simplify the C(final) by dropping the 'x' if used in this type analysis. However, if the C/Ka value is < 100 then the x-value must be retained and the solution is determined using the quadratic equation formula.

for ax² + bx + c = 0

x = b² ± SqrRt(b² - 4ac) / 2a

Name the following base: Ba(OH)2

Answers

Answer:

Caustic Base

Explanation:

"Barium hydroxide forms a strong caustic base in aqueous solution. It has many uses, e.g., as a test for sulphides; in pesticides; in the manufacture of alkali and glass. Use of barium hydroxide lime rather than soda lime, high sevoflurane concentration, high absorbent temperature, and fresh absorbent use."

==================================================================

Hope I Helped, Feel free to ask any questions to clarify :)

Have a great day!

More Love, More Peace, Less Hate.

    -Aadi x

Identify the type of reaction occurring based on the description
below:
"Sodium hydroxide reacts with iron (III) chloride."
What type of reaction is this?
a Double displacement
b
Decomposition
C Synthesis
d Combustion Reaction

Answers

Answer:double displacement

Explanation:I just did it

Please help me ........

Answers

h, i’m not entirely sure but from what i know about land and plates and how they work, h is the best answer

What are the three ways there can be a base change in a sequence?

Answers

Answer:

substitutions, deletions and insertions

What volume, in liters, does the following quantity of gas at STP occupy?

7.8*10^15

thank you

Answers

Answer:

2.9x10⁻⁷L is the volume this amount of gas occupy

Explanation:

Assuming there are 7.8x10¹⁵ atoms

Based on the general gas law:

PV = nRT

Where P is pressure = 1atm

V is volume = Our incognite

n are moles of the gas:

7.8x10¹⁵ atoms * (1mol / 6.022x10²³ atoms) = 1.30x10⁻⁸ moles of gas

R is gas constant = 0.082atmL/molK

And T is absolute temperature = 273.15K at STP

Solving for Volume:

V = nRT/P

V = 1.30x10⁻⁸ moles*0.082atmL/molK*273.15K / 1atm

V = 2.9x10⁻⁷L is the volume this amount of gas occupy

The diagram shows the electron configuration of an atom of an element for the electrons in the s and p orbitals.

What is the group number of the element in the periodic table?
A) 1
B) 2
C) 13
D) 15

Answers

Answer:

The answer would be 15, letter D.

Explanation:

Since it has 5 electrons in its outermost shell, it will be located in group 15 in the periodic table.

The electron configuration of an atom of an element for the electrons in the s and p orbitals 15th group number of the element in the periodic table option D is correct.

What is electronic configuration of 15th group?

Tha common electronic configuration of 15th group elements in ns2 np3, Group 15 elements in the modern periodic table are known as the pnictogens which means suffocation in Greek language.

This group consists of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb) and bismuth (Bi).

The group 15 elements consist of five valence electrons. Due to this the elements can either lose five electrons or gain three electrons in order to attain the stable configuration. The general electronic configuration of nitrogen family is ns 2 np 3.

therefore , because of ns2 np3 option D is correct.

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Which statement best explains why ice cubes will melt in a glass of tea?


The tea becomes saturated.

The ice cubes gain energy.

The tea’s freezing point increases.

The ice cube’s melting point decreases.

Answers

Answer:

The ice cubes gain energy

Explanation:

The ice cubes are gaining energy from the water's carbon dioxide, or H2O. They then melt because they cannot hold that energy.

How many liters of carbon dioxide will be produced at STP if 3.56 g calcium carbonate reacts completely with carbon dioxide? CaCO3 --> CaO + CO2

Answers

Answer:

V = 0.798 L

Explanation:

Hello there!

In this case, for this gas stoichiometry problem, we first need to compute the moles of carbon dioxide via stoichiometry and the molar mass of starting calcium carbonate:

[tex]3.56gCaCO_3*\frac{1molCaCO_3}{100gCaCO_3} *\frac{1molCO_2}{1molCaCO_3} =0.0356molCO_2[/tex]

Next, we use the ideal gas equation for computing the volume, by bearing to mind that the STP conditions stand for a pressure of 1 atm and a temperature of 273.15 K:

[tex]PV=nRT\\\\V=\frac{nRT}{P}\\\\V=\frac{0.0356mol*0.08206\frac{atm*L}{mol*K}*273.15K}{1atm} \\\\V=0.798L[/tex]

Best regards!

Earth's polar regions have cold, dry climates because the sun's rays are at a ?

Answers

Answer:

not reaching to the poles

Explanation:

Answer:

the rays strike at a low level in the polar region

Explanation:

okay so since the polar zones lie between 66.50 north or south the polar regions are always so cold is because strike the low parts

hope this helped!

72 drops were 1ml for stearic acid
the container was 8.5 cm wide and filled with hexane
Trial 1 was 20 drops
Trial 2 was 21
trial 3 was 16
The concentration of steric solution in hexane was :1.64*10^-4 g/ml
Area of single molecule of steric acid is: 0.21 mn^2
Molar mass of steric acid is: 284 g/mol
-What is the moles of stearic acid used?
-What is the number of stearic acid used to make the lens?
-how many molecules of stearic acid would there be if its it was 1 mole of stearic acid on that lense?

Answers

CaseAnswer:

-Mole of stearic acid used = 1.3*10^-3 mol

-Molecules of stearic acid there would be in 1 mole of stearic acid = 7.994*10^20 molecules

Explanation:

Know information from the problem are:

Mass concentration of C18H32O2 = 1.6x10^-4 g/ml, Molar mass of C18H32O2 = 284 g/mol.

Unit factor from drops to ml is 72 drops = 1ml. Therefore, for every drop, n, given, there would be n drops (1ml/ 72drops). The problem tells that stearic acid was added to hexane and that the addition process was done three-time with different amounts of drops. Think of this as releasing a substance from a burette during titration. If we convert the drops into millimeters, we would have 20 drops (1ml/72drops)= 0.28 ml, 21 drops (1ml/72drops)= 0.29 ml, and 16 drops (1ml/72drops)= 0.22 ml. [We need these volumes to determine the mass of stearic acid from mass concentration given.]

Unknown informations are:

V (volume in ml) =?

The mole of stearic acid used =?

Strategy

To calculate the mole of stearic acid used, we need the mass of stearic acid from the mass concentration. To get this we need a volume. Notice that those volumes (drops) are not the same ( it is safe to say that there is an error in the readings, as they were done independently). Therefore, we would find two or three values whose difference is smaller ( there is a little error). Subtract the smaller number from the larger number till you get a smaller difference ( do this for all three values).

The set of numbers with the smallest difference is 0.29 - 0.28=0.014, our concordant value.

Solutions

Now we us this set of numbers, 0.29-0.28, to determine an average volume :

V = (0.29-0.28)/2 (ml)

V= 0.285 ml

Now we can calculate the mass of stearic acid from the mass concentration:

m = C*V; m is the mass, C is the concentration in g/ ml, and V is the volume in ml.

m = (1.64*10^-4 g/ml)*(0.285 ml)

m = 4.674*10^-5 g

The mole of stearic acid used:

n = m/MM l; n is the mole of stearic acid, m is the mass of stearic acid, and MM is the molar mass of stearic acid.

n = 4.674*10^-5 g (284 g/mol)

n = 1.3274*10^-3

How many molecules of stearic acid would there be if it was 1 mol of stearic acid?

1 mol = 6.02214*10^23 molecule

Therefore, a conversion fraction would be:

6.02214*10^23 molecule/ 1 mol

Solution

Molecules of stearic acid in 1 mol =

1.3274*10^-3 mol (6.02214*10^23 molecule/ 1 mol)

= 7.994*10^20 molecules in 1 mol of C18H16O2

Explain what helps convert non-rich oxygen blood cells back to oxygen rich cells?

Answers

Answer:

As blood travels through the body, oxygen is used up, and the blood becomes oxygen poor. Oxygen-poor blood returns from the body to the heart through the superior vena cava (SVC) and inferior vena cava (IVC), the two main veins that bring blood back to the heart.

Explanation:

At STP (101.3 kPa, 0 °C), what volume would 2.00 moles of oxygen gas occupy? The gas constant is 8.31

Answers

Answer:

44.8 L

Explanation:

Ideal Gas Equation -

i.e.,

PV = nRT

where,

P = pressure

V = volume

n = moles

R = universal gas constant

T = temperature

Using the information given in the question, Volume of the gas can be calculated -

P = 101.3 kPa

V = ?

n = 2.00 moles

R = 8.31

T = 0 degree C = 273.15 K

Using the above data, and putting the data in the respective formula -

PV = nRT

101.3 kPa * V = 2.00 moles * 8.31 * 273.15 K

V = 44.8 L

Hence, the volume of the given gas = 44.8 L

Which of these is a learned behavior of a dog?
1.Begging for food
2.Drinking water
3.Panting on a hot day
4.Chewing on a bone

Answers

I think the answer is 2
It’s 1 begging for food is the learned behavior. panting on a hot day is not something you pick up it’s natural. Chewing on a boy is also natural. And also drinking water

What is the molar mass of Fe2(CO3)3?

Answers

Answer:

291.7167

Explanation:

The molar mass of Fe₂(CO₃)₃ is 291.714 g/mol.

To calculate the molar mass of Fe₂(CO₃)₃, we need to consider the atomic masses of the individual elements present in the compound.

The molar mass of each element is as follows:

Fe (iron): 55.845 g/mol

C (carbon): 12.011 g/mol

O (oxygen): 15.999 g/mol

Now, let's calculate the molar mass of Fe₂(CO₃)₃:

Molar mass = (2 × atomic mass of Fe) + (3 × atomic mass of C) + (9 × atomic mass of O)

Molar mass = (2 × 55.845 g/mol) + (3 × 12.011 g/mol) + (9 × 15.999 g/mol)

Molar mass = 111.69 g/mol + 36.033 g/mol + 143.991 g/mol

Molar mass = 291.714 g/mol

Therefore, the molar mass of Fe₂(CO₃)₃ is approximately 291.714 g/mol.

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The volume of a gas is 550 mL at 960 mm Hg and 200.0 C. What volume

would the pressure of the gas be 830 mm Hg if the temperature is reduced

to 150.0C? Make sure your answer is rounded to nearest whole number

and your final answer has the units of mL. *

Answers

Answer:

The volume will be 568.89 mL.

Explanation:

Boyle's law says that "The volume occupied by a given gaseous mass at constant temperature is inversely proportional to pressure"

Boyle's law is expressed mathematically as:

Pressure * Volume = constant

or P * V = k

Gay-Lussac's law indicates that when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, the pressure of the gas decreases. That is, the pressure of the gas is directly proportional to its temperature. Gay-Lussac's law can be expressed mathematically as follows:

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

Where P = pressure, T = temperature, K = Constant

Finally, Charles's law indicates that as the temperature increases, the volume of the gas increases and as the temperature decreases, the volume of the gas decreases. In summary, Charles's law is a law that says that when the amount of gas and pressure are kept constant, the quotient that exists between the volume and the temperature will always have the same value:

[tex]\frac{V}{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]

Studying an initial state 1 and a final state 2, it is fulfilled:

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

In this case:

P1= 960 mmHgV1= 550 mLT1= 200 C= 473 K (being 0 C=273 K)P2= 830 mmHgV2= ?T2= 150 C= 423 K

Replacing:

[tex]\frac{960 mmHg*550 mL}{473K} =\frac{830 mmHg*V2}{423 K}[/tex]

Solving:

[tex]V2=\frac{423 K}{830 mmHg} *\frac{960 mmHg*550 mL}{473K}[/tex]

V2= 568.9 mL

The volume will be 568.89 mL.

7. Cells often store materials like water, salts, proteins and carbohydrates in sac-like structures called A. Chloroplasts. B. Lysosomes. C. Mitochondria. D. Vacuoles.

Answers

Answer:

A

Explanation:

the chloroplast holds the water , nutrients

Answer:

[tex]\boxed {\boxed {\sf D. \ Vacuoles}}[/tex]

Explanation:

First, let's examine each answer choice.

A. Chloroplasts

These structures are only found in plant cells. They are the site of photosynthesis: the process that turns water, carbon dioxide, and light energy into glucose and oxygen.

B. Lysosomes

These help remove and break down cellular waste. They contain special enzymes that allow them to digest certain molecules, bacteria, and old parts of the cell.

C. Mitochondria

These are famously known as the powerhouse of the cell. They create energy from glucose and oxygen in a process called cellular respiration.

D. Vacuoles

Vacuoles are sacs that store substances, including water, nutrients, and waste.

Since the question asks us to pick the sac-like structures that store materials in cells, choice D: vacuoles is correct.

Neutral atoms of neon with atomic
number 10 have the same number of
electrons as
a o²+
b ca²+
c​

Answers

Answer:

d. Mg²⁺

Explanation:

c. K⁺

d. Mg²⁺

Based on the Bohr's atomic model, the atom has electrons (Mass 0; Charge -1), protons (Mass 1; Charge +1) and neutrons (Mass 1; Charge 0).

The atomic number is equal to the number of protons. That means there are 10 protons. As the Neon is netural, the amount of electrons must be 10.

A neutral atom of Mg has 12 electrons, that means the Mg²⁺ has 10 electrons the same than Ne.

Right option is:

d. Mg²⁺

10 How does no-till farming help the environment?
A It decreases soil erosion.
C It increases fertilizer use.
B It increases soil removal.
D It decreases crop yield.

Answers

Answer: Answer is A it will decrease soil erosion

Explanation:it just will trust me

Answer:

A.

Explanation:

the soil will not loosen when u till it

A parachute slows a skydiver from 85 m/s
to 45 m/s in 4.5 seconds? What is the
acceleration of the parachute?
A. 8.9 m/s2
B. -8.9 m/s
2
C. 0.1 m/s2
D. -0.1 m/s
2

Answers

Answer:

[tex]\boxed {\boxed {\sf B. \ -8.9 \ m/s^2}}[/tex]

Explanation:

Acceleration is found by dividing the change in velocity by the change in time.

[tex]a=\frac {v_f-v_i}{t}[/tex]

The parachute slows from 85 m/s to 45 m/s. Therefore, the final velocity is 45 meters per second and the initial velocity is 85 meters per second. The time is 4.5 seconds.

[tex]v_f= 45 \ m/s \\v_i= 85 \ m/s \\t= 4.5 \ s[/tex]

Substitute the values into the formula.

[tex]a= \frac {45 \ m/s- 85 \ m/s}{4.5 \ s}[/tex]

Solve the numerator and subtract.

[tex]a= \frac {-40 \ m/s}{4.5 \ s}[/tex]

Divide.

[tex]a=-8.888888889 \ m/s/s[/tex]

If we round this to the nearest tenth, the 8 in the hundredth place tells us to round the 8 up to a 9.

[tex]a \approx -8.9 \ m/s/s= -8.9 \ m/s^2[/tex]

The acceleration of the parachute is approximately -8.9 meters per square second. The value is negative because the parachute is slowing down.

francium phosphate
+ cesium acetate

Answers

Answer:

[tex]Fe_3PO_4+3Cs(CH_3COO)\rightarrow Cs_3PO_4+3Fr(CH_3COO)[/tex]

Explanation:

Hello there!

In this case, according to the given information, it is possible for us to illustrate the complete double displacement reaction between francium phosphate and cesium acetate as given on the question:

[tex]Fe_3PO_4+Cs(CH_3COO)\rightarrow Cs_3PO_4+Fr(CH_3COO)[/tex]

Which must the balanced due to the nonequal francium and cesium atoms:

[tex]Fe_3PO_4+3Cs(CH_3COO)\rightarrow Cs_3PO_4+3Fr(CH_3COO)[/tex]

Best regards!

How many liters of ammonia gas can be formed from 24.5 L of hydrogen gas at STP?

Answers

Answer:  16.3 L of ammonia gas can be formed from 24.5 L of hydrogen gas at STP

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number [tex]6.023\times 10^{23}[/tex] of particles.

The balanced chemical equation is:

[tex]3H_2+N_2\rightarrow 2NH_3[/tex]

According to stoichiometry :

[tex]3\times 22.4=67.2L[/tex] of [tex]H_2[/tex]  produce = [tex]2\times 22.4=44.8L[/tex] of [tex]NH_3[/tex] at STP

Thus 24.5 L of [tex]H_2[/tex]  will produce= [tex]\frac{44.8}{67.2}\times 24.5=16.3L[/tex] of [tex]NH_3[/tex] at STP

Thus 16.3 L of ammonia gas can be formed from 24.5 L of hydrogen gas at STP

A student prepares four different aqueous NaCl solutions according to the table. Which solution will have the highest molarity?

Answers

Answer:

what did you end up guessing

Explanation:

PLEASE HELP!! 15 POINTS!
What could the fourth quantum number of a 2s^2 electron be?

Answers

Answer:

option D

Explanation:

first quantum number of a 2s2

n = 2

second quantum number of a 2s2

l = 0 to n-1

l = 0, 1

For s orbital

l = 0

third quantum number of a 2s2

ml = - l to +l

ml = 0

fourth quantum number of a 2s2 electron be

?½ = spin down

½ = spin up

2s2 has 2 electrons 1 spin down and 1 spin up (starts with spin down)

ms = +1/2

Answer:

+1/2

Explanation:

Can someone help me ❤️❤️❤️

Answers

Answer:

i think the answer would be C

Explanation:

no matter what you do to the jar the mass will stay the same. unless you add more nails

How did the us stop the spread of communism during the Cold War

Answers

Answer:

With the policies of containment, the United States hoped to effectively stop the spread of communism and their newest threat. After the war, the United States and the Soviet Union had very different ideas on how to rebuild.

WILL MARK BRAINLEST

Which of the following are sources of greenhouse gasses? Select all that apply



a

Bike Riding

b

Cow Farts

c

Growing Trees

d

Burning Coal

e

Car Exhaust

Answers

Answer:

b and c

Explanation:

sorry if i'm wrong

Answer:

b, c, d, e

Explanation:

Which of the following are also compounds? Select all that apply.


A.
CuFeS2


B.
H2O


C.
KCl


D.
Mg


E.
Cl

Answers

Answer:

option B,C and A are compound

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