How many atoms in 3.6 g of lead (Pb) ? image attached , will give brainliest

Answer:

water is a liquid

Explanation:

WATERRRDR ISSS A LIQUIIIDD

Water is a compound. A compound is made of two or more different elements chemically bonded together. Water is made up of two hydrogen molecules and one oxygen molecule.

Answer:

Nighttime temperatures would be greatly reduced.

Explanation:

Answer:

Chemical because it alters the identity of the substance

Answer:

11.58 L of N₂

Explanation:

We'll begin by calculating the number of mole in 37.2 g of magnesium. This can be obtained as follow:

Mass of Mg = 37.2 g

Molar mass of Mg = 24 g/mol

Mole of Mg =?

Mole = mass /Molar mass

Mole of Mg = 37.2 / 24

Mole of Mg = 1.55 moles

Next, we shall write the balanced equation for the reaction. This is illustrated below:

3Mg + N₂ —> Mg₃N₂

From the balanced equation above,

3 moles of Mg reacted with 1 mole of N₂.

Therefore, 1.55 moles of Mg will react with = (1.55 × 1)/3 = 0.517 mole of N₂

Thus, 0.517 mole of N₂ is need for the reaction.

Finally, we shall determine the volume of N₂ needed for the reaction as follow:

Recall:

1 mole of a gas occupies 22.4 L at STP.

1 mole of N₂ occupied 22.4 L at STP.

Therefore, 0.517 mole of N₂ will occupy = 0.517 × 22.4 = 11.58 L at STP

Thus, 11.58 L of N₂ is needed for the reaction.

The volume of nitrogen gas is 11.58 L of N₂

Mole = mass /Molar mass

= 37.2 / 24

= 1.55 moles

Now

1.55 moles of Mg will react with

= (1.55 × 1)/3

= 0.517 mole of N₂

Thus, 0.517 moles of N₂ is needed for the reaction.

Now

1 mole of a gas occupies 22.4 L at STP.

So,

Nitrogen gas is

= 0.517 × 22.4

= 11.58 L at STP

Learn more about the gas here: https://brainly.com/question/3134912

Answer: In gases the particles move rapidly in all directions, frequently colliding with each other and the side of the container. With an increase in temperature, the particles gain kinetic energy and move faster. The actual average speed of the particles depends on their mass as well as the temperature – heavier particles move more slowly than lighter ones at the same temperature. The oxygen and nitrogen molecules in air at normal room temperature are moving rapidly at between 300 to 400 metres per second. Unlike collisions between macroscopic objects, collisions between particles are perfectly elastic with no loss of kinetic energy.

Explanation:  This is very different to most other collisions where some kinetic energy is transformed into other forms such as heat and sound. It is the perfectly elastic nature of the collisions that enables the gas particles to continue rebounding after each collision with no loss of speed. Particles are still subject to gravity and hit the bottom of a container with greater force than the top, and giving gases weight. Hope this helps with your problem! Byeeee :DDD

It's sad seeing people actually helping you lol.

and then you dont give brainliest. like ever.

Answer:

2 g

Explanation:

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

Original amount (N₀) = 16 g

Time (t) = 21.6 s

Amount remaining (N) =?

Next, we shall determine the number of half-lives that has elapse. This can be obtained as follow:

Time (t) = 21.6 s

Half-life (t½) of ¹⁶N = 7.13 s

Number of half-lives (n) =?

n = t / t½

n = 21.6 / 7.13

n = 3

Finally, we shall determine the amount of ¹⁶N remaining. This can be obtained as follow:

Original amount (N₀) = 16 g

Number of half-lives (n) = 3

Amount remaining (N) =?

N = 1/2ⁿ × N₀

N = 1/2³ × 16

N = 1/8 × 16

N = 2 g

Thus, the amount of ¹⁶N remaining is 2 g

Answer:

oxygen and glucose

Explanation:

Photosynthesis produces oxygen and glucose. Glucose is a sugar which serves as "food" for the plant, and oxygen is just a by-product of the reaction.

Answer:

75.37 g

Explanation:

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

Percentage of nitrogen (N) in the compound = 36.86 %

Mass of nitrogen (N) in the compound = 44 g

Mass of oxygen (O) in the compound =?

Next, we shall determine the total mass of the compound. This can be obtained as follow:

Percentage of nitrogen (N) in the compound = 36.86 %

Mass of nitrogen (N) in the compound = 44 g

Total mass of compound (T) =?

Percentage of N = mass of N/ total mass × 100

36.86 % = 44 / T

36.86 / 100 = 44 / T

Cross multiply

36.86 × T = 100 × 44

36.86 × T = 4400

Divide both side by 36.86

T = 4400 / 36.86

Total mass = 119.37 g

Next, we shall determine the percentage of oxygen in the compound. This can be obtained as follow:

Percentage of N = 36.86 %

Percentage of O =?

Percentage of O = 100 – 36.86 %

Percentage of O = 63.14 %

Finally, we shall determine the mass of oxygen in the compound. This can be obtained as follow:

Percentage of O = 63.14 %

Total mass = 119.37 g

Mass of O =.?

Percentage of O = mass of O / total mass × 100

63.14 % = Mass of O / 119.37

Cross multiply

Mass of O = 63.14 % × 119.37

Mass of O = (63.14 / 100)× 119.37

Mass of O = 75.37 g

Thus, the mass of oxygen in the compound is 75.37 g

Answer:

[tex]6.15x10^2[/tex]

Explanation:

Hello!

In this case, when performing mathematical operations with numbers in scientific notation, the first step is to write them in standard notation:

550 - 65.0

Thus, the result without any significant figures-based analysis is:

615.0

However, since 550 is significant to the ones and 65.0 to the tenths, we need to round the result to the bigger significance, in this case to the ones; therefore the appropriate result would be:

615

That in scientific notation would be:

[tex]6.15x10^2[/tex]

Best regards!

Answer:

dt = 4.32°C

Explanation:

Given the following data;

Mass = 16.33g

Quantity of heat, Q = 63.4J

Specific heat capacity = 0.899 J/g °C

To find the temperature change;

Heat capacity is given by the formula;

[tex] Q = mcdt[/tex]

Where;

Making dt the subject of formula;

[tex] dt = \frac {Q}{mc} [/tex]

Substituting into the equation, we have;

[tex] dt = \frac {63.4}{16.33*0.899} [/tex]

[tex] dt = \frac {63.4}{14.6807} [/tex]

dt = 4.32°C

Therefore, the change in temperature for this aluminum is equal to 4.32°C.

Answer:

same density

Explanation:

The amount of methanol is a quantitative characteristic, and by the other side the density of methanol is a qualitative characteristic. What I mean is that the amount of methanol is not related to the density; it would be the same density no matter how much methanol you have.

Answer: 1.6x10^22

Explanation: H2O —> H2 + 1/2O2 so half the number of water molecules

Answer:

16.0 mol H.

Explanation:

Hello!

In this case, since the Avogadro's number help us to compute the moles of methanol in the given molecules:

[tex]n_{CH_3OH}=2.41x10^{24}molecCH_3OH*\frac{1molCH_3OH}{6.022x10^{23}molecCH_3OH}=4.00molCH_3OH[/tex]

Thus, since 1 mole of methanol contains 4 moles of hydrogen atoms, we obtain:

[tex]n_H=4.00molCH_3OH*\frac{4molH}{1molCH_3OH}\\\\n_H=16.0molH[/tex]

Best regards!

Answer:

Experiments to determine mechanisms involve looking at indirect evidence to help support or disprove a proposed mechanism.

Most intermediates are not typically isolated to determine reaction mechanisms.

Carbocations are very reactive and are typically not isolated for analysis.

Scientists can prove that a specific mechanism exists.

Evidence of intermediates sometimes can be seen using techniques such as nuclear magnetic resonance spectroscopy

Explanation:

The study of reaction mechanism and chemical kinetics often form the main thrust of study in organic, inorganic and physical chemistry.

We often want to know the actual processes involved in the conversion of one specie to another. Unfortunately, this information may have to be obtained indirectly by certain chemical reactions or by the use of new instrumental methods such as nuclear magnetic resonance spectroscopy.

Many organic reactions have carbocation intermediates. These carbocations are relatively short-lived and are transient intermediates which are rarely isolated unless they are isolated in a molecular cage using a macromolecule or in superacids.

By intensive study, scientists can proof or disprove the authenticity of any proposed mechanism.

We must know that a transition state has partial bonds. It is often an extremely short-lived specie which cannot be isolated.

Answer:

I-

Explanation:

Draco was better. Harry didn’t act too much like a main character and was kinda boring.. while Draco’s personality fit the role he played as the bully/mean kid and he still kept me interested.

Answer:

Not all conflicts are harmful to an organization

Explanation:

Not all conflicts in an organization are harmful to that organization.

Conflicts can be good for an organization. Even though conflicts may always seem difficult, they could bring about growth and changes which are good for all organizations.

Conflict may have positive or negative results when they occur. How these conflicts are approached is what determines the result.

Positive conflict can be constructive, it births new ideas, gives opportunities for creativity and skills expansion and can solve continuous problems.

Answer:

78.8 mL .

Explanation:

Ba( NO₃ )₂ ⇄ Ba⁺² + 2 NO₃⁻

1 mole                        2 mole

261 mL of .272 M in nitrate contains .261 x .272 gram -ions ( moles ) of NO₃⁻

= .071 gram-ions .

Let the volume of Ba(NO₃)₂ required be v litre .

moles of Ba( NO₃ )₂ in v volume = v x .45 moles

v x .45 moles of Ba( NO₃ )₂ will give 2 x  v x .45 moles of NO₃⁻

According to question

2 x  v x .45 =  .071

v = .07888 litre

= 78.8 mL .

Answer:

The mixture quickly foams up with carbon dioxide gas. If enough vinegar is used, all of the baking soda can be made to react and disappear into the vinegar solution. The reaction is: Sodium bicarbonate and acetic acid reacts to carbon dioxide, water and sodium acetate.

Explanation:

hope this helps

Answer:

0.0084

Explanation:

The mole fraction of BaCl₂ (X) is calculated as follows:

X = moles BaCl₂/total moles of solution

Given:

moles of BaCl₂ = 0.400 moles

mass of water = 850.0 g

We have to convert the mass of water to moles, by using the molecular weight of water (Mw):

Mw of water (H₂O) = (2 x 1 g/mol)+ 16 g/mol = 18 g/mol

moles of water = mass of water/Mw of water = 850.0 g/(18 g/mol) = 47.2 mol

The total moles of the solution is given by the addition of the moles of solute (BaCl₂) and the moles of solvent (water):

total moles of solution = moles of BaCl₂ + moles of water = 0.400 + 47.2 mol = 47.6 mol

Finally, we calculate the mole fraction:

X = 0.400 mol/47.6 mol = 0.0084

Answer:

The numder of moles of 7.89*10¹¹ atoms of Carbon is 1.31*10⁻¹².

Explanation:

Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023*10²³ particles per mole. Avogadro's number represents a quantity without an associated physical dimension, so it is considered a pure number that allows describing a physical characteristic without an explicit dimension or unit of expression. Avogadro's number applies to any substance.

Then you can apply the following rule of three, if by definition of Avogadro's number 6.023*10²³ atoms are present in 1 mole of Carbon, 7.89*10¹¹ atoms will be present in how many moles?

[tex]amount of moles=\frac{1 mole*7.89*10^{11} }{6.023*10^{23} }[/tex]

amount of moles=1.31*10⁻¹²

The numder of moles of 7.89*10¹¹ atoms of Carbon is 1.31*10⁻¹².

Answer:

12.7 mol

Explanation:

A chemist measures the amount of fluorine gas produced during an experiment. He finds that 482. g of fluorine gas is produced. Calculate the number of moles of fluorine gas produced.

Step 1: Given data

Mass of fluorine (m): 482. g

Step 2: Determine the molar mass (M) of fluorine

Fluorine is a diatomic molecule of chemical formula F₂. Its molar mass is:

mF₂ = 2 × mF = 2 × 19.00 g/mol = 38.00 g/mol

Step 3: Determine the number of moles (n) corresponding to 482. g of fluorine

We will use the following expression,.

n = m/M

n = 482. g/(38.00 g/mol)

n = 12.7 mol

Answer:

The correct answer is option B, that is, CO + H2O → H2 + CO2

The redox reactions are regarded as the chemical reactions in which one reactant goes through the process of reduction and one reactant goes through the process of oxidation. The reduction reactions are the reactions in which gain of electrons occurs, while oxidation reactions are the reactions in which loss of electrons occurs.  

From the mentioned options, only option B, that is, CO + H2O → H2 + CO2 is a kind of redox reaction. In this, the carbon is getting oxidized from +2 to +4 oxidation state, and hydrogen is getting reduced from +1 to 0 oxidation state. Hence, this reaction can be regarded as a redox reaction.

Explanation:

Answer:

its ice cream

Explanation

im taking the exam <3 and there is more blue on the the graph then any other color so its queit obv.

I think this statement is True.

Answer:

Explanation:

20.1 mL of .3 M KOH reacts with .38 g of sample monoprotic acid

20.1 mL of .3 M KOH = .021 x .3 mole of KOH

= .0063 mole of KOH

.0063 mole of KOH will react with .0063 mole of monoprotic acid

.0063 mole of monoprotic acid = .38 g

1 mole of monoprotic acid = 60.3 or 60 g

molecular weight of monoprotic acid = 60

Acid contains 1.6 % H , 22.2 % N , 76.2 % O

Ratio of weight of H , N , O in sample

= 1.6 : 22.2 : 76.2

Ratio of moles of H , N , O

1.6 / 1 : 22.2 / 14 : 76.2 / 16

1.6 : 1.585 : 4.76

= 1.6 / 1.585 : 1 : 4.76 / 1.585

= 1 : 1 : 3

Empirical formula

= HNO₃

Mol formula = [tex](HNO_3)_n[/tex] ( let )

Mol weight = n ( 1 + 14 + 3 x 16 )

= 63n  .

Mol weight calculated above = 60

63n = 60

n = 1 ( approx )

Mol formula = HNO₃

Mol mass =   63 .

Answer:

Important industrial processes often utilize solution chemistry. The substance present in the major proportion is called the solvent, whereas the substance present in the minor proportion is called the solute.

Explanation:

Answer:

I think that it might be C. I'm not an expert so please don't blame me, I'm sorry if i'm wrong!

Explanation: