Learning task 1: as you start exploring the subject answer the following question write your answer on your answer sheet

need help pls ​

Answer:

8.82 gm of Pb

Explanation:

Question

calculate the Mass of lead that will be deposited from an aqueous solution of lead(2)salt by the same quantity of electricity that deposit 2.7 g of copper from an aqueous solution of copper (2)salt​Since the oxidation# of the Pb and the Cu is the same, we know that the same amount of electricity that will deposit 1 mole of Cu will deposit 1 mole of Pb

2.7 gm of Cu were deposited

the atomic mass of Cu = 63.5

the  number of moles of Cu deposited was 2.7/63.5 = 0.0425 moles

so 0.0425 moles of Pb will be deposited.

The atomic mas of Pb is 207.2

0.0425 mole of Pb weigh 0.0425 X 207.2 =

8.82 gm of Pb

Answer:

The amount of heat needed is 593.88 kJ.

Answer:

The negative ion is larger than the original atom. but the same number of positive protons, the size of the ionic radius will increase. When an atom has its electrons attracted to another atom it becomes a positive ion. The positive ion is smaller than the original atom.

Answer:

B)

Explanation:

Taking into account the definition of pH and pOH, the mass of LiOH needed to be dissolved in 500.0 mL of water to produce a solution with a pH of 12.40 is 0.299375 grams.

First of all, pH is a measure of acidity or alkalinity that indicates the amount of hydrogen ions present in a solution or substance.

The pH is defined as the negative base 10 logarithm of the activity of hydrogen ions, that is, the concentration of hydrogen ions or H₃O⁺:

pH= - log [H⁺]= - log [H₃O⁺]

Similarly, pOH is a measure of hydroxyl ions in a solution and is expressed as the logarithm of the concentration of OH⁻ ions, with the sign changed:

pOH= - log [OH⁻]

The following relationship can be established between pH and pOH:

pOH + pH= 14

In this case, being pH= 12.40, pOH is calculated as:

pOH + 12.40= 14

pOH= 14 - 12.40

pOH= 1.60

Replacing in the definition of pOH the concentration of OH⁻ ions is obtained:

- log [OH⁻]= 1.60

Solving:

[OH⁻]= 10⁻¹ ⁶

[OH⁻]= 0.025 M

Then, the [OH⁻] is 0.025 M.  

Strong bases are bases that completely dissociate in water into the cation and OH - (hydroxide ion). LiOH is a strong base, so the OH- concentration is equal to the LiOH concentration:

[OH⁻]= [LiOH]= 0.025 M

Finally, Molarity or Molar Concentration is the number of moles of solute that are dissolved in a certain volume:

[tex]Molarity=\frac{number of moles}{volume}[/tex]

In this case, knowing that molarity is 0.025 M and the volume is 500 mL= 0.5 L, you can replace in the expression for molarity:

[tex]0.025 M=\frac{number of moles}{0.5 L}[/tex]

Solving:

number of moles= 0.025 M× 0.5 L

number of moles= 0.0125 moles

Finally, since the molar mass of LiOH is 23.95 [tex]\frac{g}{mol}[/tex], that is, the amount of mass that the substance contains in one mole, the mass of LiOH that 0.0125 mol contains can be calculated as:

0.0125 mol×23.95 [tex]\frac{g}{mol}[/tex]= 0.299375 g

The mass of LiOH needed to be dissolved in 500.0 mL of water to produce a solution with a pH of 12.40 is 0.299375 grams.

Learn more:

Answer:

Mark me as brainlest

Explanation:

Microorganisms present in our body Re viruses, bacteria, fungi, algae, and protozoa among which most of them cause immense benefits to the body. There are some harmful microorganisms too known as pathogens which cause disease and cause a threat to all existing life forms of the earth which can result in death at times.

Answer:

An example of microorganisms acting in a harmful way is a bacteria spoiling food.

Answer: 4,2

The graph should show how to do it.

Answer:

boi i need the choices idiot

Explanation:

Nobody can add an answer without context.

But if this helps,

"Vaporization of an element or compound is a phase transition from the liquid phase to vapour. There are two types of vaporization: evaporation and boiling. Evaporation is a surface phenomenon, whereas boiling is a bulk phenomenon." - Wikipedia

https://en.wikipedia.org/wiki/Vaporization

Answer:

4 covalent bonds

Answer: It just haven’t been discovered yet

Explanation:

Because the periodic table was discovered long ago some elements haven’t been discovered thats why it maybe has 3 columns

Answer:

accelerating upward would be your answer

Answer:

its for sure not b. its c the crust and upper part of the mantle.

the whole definition:

the rigid outer part of the earth, consisting of the crust and upper mantle.

Answer:

The Group 7A elements have seven valence electrons in their highest-energy orbitals (ns2np5). This is one electron away from having a full octet of eight electrons, so these elements tend to form anions having -1 charges, known as halides: fluoride, F-; chloride, Cl-, bromide, Br-, and iodide, I-.

...

Group 7A — The Halogens.

(7)

(8)

(9)

(10)

Explanation:

here is your answer hope you will enjoy and mark me as brainlist

thank you

The enthalpy of reaction for the hydrogenation of propene to propane is -926 kJ/mol.

The bond energy of a molecule is obtained as the sum of the bond energies of all the bonds between atoms in the molecule. The heat of reaction can be obtained using the relation;

∆Hrxn = ∑Bonds being broken - ∑Bonds being formed

Hence, we have;

Where all the energies are quoted in KJ/mol

C=C = 598

C - C = 346

H - H = 436

C - H = 416

For the reaction;

CH₂CHCH₃(g) + H₂(g) → CH₃CH₂CH₃(g)

∆Hrxn = ∑[6(C - H) + 1(C=C) + 1(C - C)] -  ∑[3(C - C) + 8(C - H)

∆Hrxn = [6(416) + 1(598) + 1(346)] - [3(346) + 8(416)]

∆Hrxn =3440 - 4366 = -926 kJ/mol

Learn more: https://brainly.com/question/13440572

Answer:

a fruit and oatmeal bar contains 142000 calories.

A nutritional calorie, or kilocalorie, is equal to 1000 calories.

E = 142 kcal · 1000 cal/kcal.

E = 142 000 cal.

Calorie (cal), or small calorie, is the amount of energy needed to heat one gram of water by one degree Celsius.

One small calorie is approximately 4.2 joules.

A calorie is a unit of energy.

Explanation:

hope it helps  :)

By definition, the pair corresponding to the Brønsted-Lowry base is H₂O/H₃O⁺.

According to Brønsted-Lowry, acids and bases were defined in terms of the transfer of hydrogen ions, H+.

A compound that donates a proton to another compound is called a Brønsted-Lowry acid, and a compound that accepts a proton is called a Brønsted-Lowry base.

An acid-base reaction is, therefore, the transfer of a proton from a donor (acid) to an acceptor (base).

On the other hand, when an acid donates an H+, the resulting species is called the conjugate base of the acid because it reacts as a proton acceptor in the reverse reaction. Also, when a base accepts H+, it becomes its conjugated acid.

So, in this case, the pair corresponding to the Brønsted-Lowry base is H₂O/H₃O⁺.

Learn more:

Answer:

The volume of the liquid should be measured before it is heated.  

Explanation:

Because During an experiment to test how a variable changes a substance, it is important to first observe and record the characteristics of the substance before the variable is introduced. In this case, the variable is heat energy.  

Answer:

Melting and evaporation both represent changes in matter that involve behavior at the molecular level.

Answer:

well both disappear over time

Explanation:

2 solutions of NaOH and H₂SO₄ at 29.5 °C are mixed in a coffee-cup calorimeter and after the reaction is completed the temperature is 35.8 °C. The increase in the temperature is 6.3 °C.

To determine the heat of neutralization, Chelsea used a coffee-cup calorimeter.

Initially, she had 2 solutions, NaOH and H₂SO₄, both at 29.5 °C. Upon mixing, the heat was evolved and the final temperature of the solution was 35.8 °C. The neutralization reaction was:

NaOH + H₂SO₄ ⇒ Na₂SO₄ + H₂O

The increase in temperature (ΔT) is equal to the difference between the final temperature and the initial temperature.

[tex]\Delta T = 35.8 \° C - 29.5 \° C = 6.3 \° C[/tex]

This data can be used to calculate the heat of neutralization (q) using the following expression.

[tex]q = c \times m \times \Delta T[/tex]

where,

2 solutions of NaOH and H₂SO₄ at 29.5 °C are mixed in a coffee-cup calorimeter and after the reaction is completed the temperature is 35.8 °C. The increase in the temperature is 6.3 °C.

Learn more: https://brainly.com/question/4040029

Answer: The quantitative interpretation of the reaction is as follows: 84.01 g (1 mol) of sodium

bicarbonate reacts with 36.46 g (1 mol) of hydrochloric acid to generate 58.44 g (1 mol) of salt,

18.02 g (1 mol) of water, and 44.01 g (or 1 mol) of carbon dioxide. Of course the starting

quantity of NaHCO3 may be more or less than 84.01 g, but a proportionate quantity of the

hydrochloric acid will be consumed, and proportionate quantities of the products will be formed.

For example, should 100.00 g of NaHCO3 react with excess acid, the theoretical mass of salt

produced would be calculated as follows:

58.44 g sodium chloride 100.00 g sodium bicarbonate

84.01 g sodium bicarbonate = 69.55 g sodium

chloride

Note that when a bicarbonate is reacted with excess acid, the salt produced is the only substance

not readily volatile. That is, the unreacted acid, the water, and the carbon dioxide are easily

removed by heating. Does this help?

Answer:

0.02 moles of O₂ will be leftover.

Explanation:

Answer:

1.377

Explanation:

Because we are subtract the initial from the final

Answer:

see explanation

Explanation:

How much is 1 mole of something?

O A. 6.02 x 10

O B. 6.02 x 10-23

O C. 6.02 × 23

O D. 6.02 x 1023

look carefully at your picture

use a magnifying glass if you need to

I am rewriting the choices the way it appears i  your picture

A. 6.02  X 10

B 6.02 X 10^-23

C. 6.02^23

D. 6.02 X 10^23

the answer is D. you left out "to the pow......"  

a significant mistake

what is in your picture is 6.02 X 10^23 and means

6.02 X 100,000,000,000,000,000,000,000

what you wrote 6.02 X 1023 means 6158

when we are talking about the number of teensy tiny atoms in a measurable mass we are talking BIGGGGG  GIANTTTTT numberswhen written correctly, the answer is D

Answer: Chloroplast

Explanation:

We have that for the Question "When the volume of a closed container containing hydrogen gas is increased by a factor of two, how will this affect the number of hydrogen atoms in the container"

Answer:

Explanation:

The number of hydrogen atoms will remain the same in the container. Because the container is closed and amount of hydrogen gas remains constant, which means that no extra amount of hydrogen gas is removed or added from the container when volume increases.

For more information on this visit

https://brainly.com/question/17756498

Answer:

Explanation:

1.08kg/50.5 cm^3(1000g/kg)=21.386 g/cm^3

Answer:

[tex]\boxed {\boxed {\sf 21.4 \ g/cm^3}}[/tex]

Explanation:

We are asked to find the density of an object.

The density of a substance is its mass per unit volume. It is calculated by dividing the mass by the volume.

[tex]\rho= \frac{m}{v}[/tex]

The mass of the object is 1.08 kilograms. The object displaced 50.50 cubic centimeters of water, so this value is its volume.

We are asked to give the density in grams per cubic centimeter, so we must convert the mass. There are 1000 grams in 1 kilogram. Set up a conversion factor.

[tex]\frac {1000 \ g}{1 \ kg}[/tex]

Multiply by the given mass: 1.08 kg

[tex]1.08\ kg *\frac{1000 \ g }{ 1\ kg}[/tex]

The units of kilograms cancel.

[tex]1.08*\frac{1000 \ g }{1}[/tex]

[tex]1.08*{1000 \ g } = 1080 \ g[/tex]

Now we know the mass in grams and the volume:

Substitute the values into the density formula.

[tex]\rho= \frac{1080 \ g }{50.50 \ cm^3}[/tex]

Divide.

[tex]\rho= 21.3861386 \ g/cm^3[/tex]

The original measurements of mass and density have 3 and 4 significant figures. Our answer must have the least number of significant figures, or 3.

For the number we found, that is the tenths place. The 8 in the hundredth place tells us to round the 3 in the tenths place up to a 4.

[tex]\rho \approx 21.4 \ g/cm^3[/tex]

The density of the object is approximately 21.4 grams per cubic centimeter.

Answer:

can you include the choices?

Explanation:

Answer:

Answer b: The law of conservation of matter says that in chemical reactions, the total mass of the products must equal the total mass of the reactants.

Explanation:

hope this helps

Answer:

6 carbon atoms, 12 hydrogen atoms and 6 oxygen atoms

Explanation:

Answer:

Sulfur

Explanation:

Using this to make the answer 20 characters long