I need help please i need to turn this in today

Answer:

There were originally 8 atoms of Potassium-40.

Explanation:

The half-life of a radioactive material is the time taken for half the original material to decay or the time required for a quantity of the radioactive substance to reduce to half of its initial value.

If the original material formed without any Argon-40, it means that the atoms originally present were Potassium-40 atoms.

Presently, there are 7 Argon-40 atoms for every 1 of Potassium-40, we can deduce the number of half-lifes the Potassium-40 has undergone as follows :

After one half-life, (1/2) there will be one Potassium-40 atom for every Argon-40 atom.

After a second half life, 1/2 × 1/2 = 1/4: there will be one Potassium-40 atom for every three atoms of Argon-40.

After a third half-life, 1/4 × 1/2 = 1/8: there will be one Potassium-40 atom for every 7 atoms of Argon-40.

Since there are 1/8 atoms of Potassium-40 presently, there were originally 8 atoms of Potassium-40.

Answer:

B

Explanation:

Weathering is the physical and chemical breakdown of rock at the earth's surface. ... The physical breakdown of rock involves breaking rock down into smaller pieces through mechanical weathering processes. These processes include abrasion, frost wedging, pressure release (unloading), and organic activity.

Answer:

The mass of sodium metal that must be introduced to water to produce 3.3 grams of hydrogen gas, H₂, is approximately 18.82 grams of sodium metal

Explanation:

The given mass of hydrogen gas produced = 3.3 grams

The molar mass of hydrogen gas, H₂ = 2.016 g/mol

The number of moles of hydrogen gas in 3.3 grams of H₂, 'n', is given as follows;

n = Mass/(Molar mass)

n = 3.3 g/(2.016 g/mol) = 1.63690476 moles of H₂

The reaction of sodium and water can be written as follows;

2Na + 2H₂O → 2NaOH + H₂ (g)

2 moles of sodium produces 1 mole of hydrogen gas, H₂

Therefore;

1.63690476/2 moles of sodium will produce 1.63690476 moles of hydrogen gas, H₂

The molar mass of sodium, Na ≈ 22.989 g/mol

The mass of 1.63690476/2 moles of sodium, 'm', is given as follows;

m = 1.63690476/2 moles × 22.989 g/mol ≈ 18.8154018 grams ≈ 18.82 grams

The mass of sodium that will produce 3.3 grams of hydrogen, m ≈ 18.82 grams of sodium metal.

Answer:

The volume of solution in liters required to make a 0.250 M solution from 3.52 moles of solute is 14.08 liters of solution

Explanation:

The question relates to the definition of the concentration of a solution which is the number of moles per liter (1 liter = 1 dm³) of solution

Therefore we have;

The concentration of the intended solution = 0.250 M

Therefore, the number of moles per liter of the required resolution = 0.250 moles

Therefore, the concentration of the required solution = 0.250 moles/liter

The volume in liters of the required solution that will have 3.52 moles of the solute is given as follows;

The required volume of solution = The number of moles of the solute/(The concentration of the solution)

∴ The required volume of solution = 3.52 moles/(0.250 moles/liter) = 14.08 liters

The required volume of solution to make a 0.250 M solution from 3.52 moles of solute = 14.08 liters.

Therefore the number of liters required to make a 0.250 M solution from 3.52 moles of solute = 14.08 liters.

Answer:

mhm

Explanation:

Answer:

588 mole

29.4

+29.4

5 8. 8g

A forecaster studying the climate of an area would find average yearly precipitation most helpful.

Forecaster studying of climate tells about the changes which will occur in the atmosphere in the upcoming future time.

Forecasting is done by measuring various environmental factors for the prediction of atmosphere. As it will given information about the percent of rainfall in the upcoming days, amount of precipitation, snowfall and so on.

Hence, option (A) is correct.

To know more about Forecaster studying of climate, visit the below link:
https://brainly.com/question/13407372

Answer:

temperature

catalyst

surface area

Answer:

humans or animals

Explanation:

Answer: m = nM= 242.8 g

Explanation: amount of MgCl2 is same as n(Mg)

M(MgCl2) = 95.21 g/mol

95.21 g/mol is the mass in grams of MgCl[tex]_2[/tex] are produced by 2.55 mol Mg in the reaction Mg + 2HCl ⟶ MgCl[tex]_2[/tex] + H[tex]_2[/tex].

A body's mass is an inherent quality. Prior to the discoveries of the concept of atom as well as particle physics, it was widely considered to be tied to the amount of matter inside a physical body. It was discovered that, despite having the same quantity of matter in theory, different atoms and elementary particles have varied masses.

There are various conceptions of mass in contemporary physics that are theoretically different but physically equivalent. The resistance of the body to accelerate (change of velocity) in the presence of a net force can be measured experimentally as mass. The gravitational pull an object has on other bodies is also influenced by its mass.

m = n×M= 242.8 g

M(MgCl[tex]_2[/tex]) = 95.21 g/mol

Therefore, 95.21 g/mol is the mass in grams of MgCl[tex]_2[/tex] are produced by 2.55 mol Mg in the reaction Mg + 2HCl ⟶ MgCl[tex]_2[/tex] + H[tex]_2[/tex].

To know more about mass, here:

https://brainly.com/question/28704035

#SPJ2

Answer:

9.2288 L

Explanation:

The equation of the reaction is given as;

2 Ca(NO3)2 → 2 CaO + 4 NO2 + O2

From the reaction;

2 mol of Ca(NO3)2 produces 4 mol of NO2

Converting 33.8g to Number of moles;

Number of moles = Mass / Molar mass

Number of moles = 33.8 g / 164.088 g/mol

Number of moles = 0.206 mol

2 = 4

0.206 = x

Solving for x;

x = 0.206 * 4 / 2

x = 0.412 mol

At STP;

1 mol = 22.4 L

0.412 mol = x

Solving for x;

x = 0.412 * 22.4 = 9.2288 L

Answer:

40.5 g/mL

Explanation:

Density is a measure of a substance's mass over its volume.

d = m/v

Therefore d = 255.15g/6.3mL = 40.5 g/mL

Answer:

Answer:

A violent reaction will occur and zinc sulphide is formed as a product

Answer:

156748

Explanation:

The first number is on the magnetism card 1

The combination  contains only the numbers found on the cards showing techniques to separate mixtures 1,5,6,7,8

The last number is on the filtering card

The red is in the middle half of 8 is 4

The plants are the part that absorb the Sun's light and heat.

The part of a food chain that absorbs the sun's light and heat is producers that are plants.

A food chain is the chain that shows the transfer of energy from one part to another.

The bottom of the food chain is the producers that make their own food, then the consumers and the decomposers.

Thus, the part of a food chain that absorbs the sun's light and heat is producers that are plants.

Learn more about food chain

https://brainly.com/question/16065961

#SPJ2

Answer:

Yes

Explanation:

Answer:

V=f*(wavelength)

V= (800)(20m)

16000m/s

Explanation:

Explanation:

The answer to the question is (3) K2SO4

Model 1 is an ion; Model 3 is an isotope identifies the models that represent an ion and an isotope of the original atom. Therefore, option A is correct.

Isotopes are atoms that have the same number of protons but different numbers of neutrons. They have nearly identical chemical properties but differ in mass and thus in physical properties.

Neutrons exist to stabilize the nucleus without them, the nucleus would be nothing more than a cluster of positively charged protons. There are different isotopes because there are different ways of stabilizing the protons.

Model 1 is an ion and Model 3 is an isotope identifies the models that represent an ion and an isotope of the original atom. The image of the model is attached below:

Thus, option A is correct.

To learn more about the model, follow the link;

https://brainly.com/question/12955625

#SPJ2

The molecular formula for Nickel (IV) Chloride will be NiCl₂. Nickel reacts with chloride to form a salt. The salt is yellow in color and anhydrous.

A molecular formula is a way of presentation of chemical formula of a compound. It gives the information related to the type of atoms, number of atoms which constitutes the compound and the chemical properties.

Molecular formula of a chemical compound can be derived by the valency of element. In this question, molecular formula of the compound can be derived by:

Valency of Nickel = 2

Valency of Chlorine = 1

By the cross-multiplication of valency:

element 1(valency of element 2). element 2 (valency of element 1)

= Ni (1). Cl(2)

= NiCl₂

Therefore, the molecular formula of Nickel (IV) chloride will be NiCl₂.

Learn more about molecular formula here:

https://brainly.com/question/14425626

#SPJ2

Answer:

jupiter is your answer

Explanation:

you weigh more there

Answer: in a straight path!

Explanation: hope this helps

Answer:

290

Explanation:

Temperature in kelvin = 273 + Temperature in ⁰C

Answer: °Celsius Kelvin

                25.00    298.15

                25.01 298.16

                25.02 298.17

                25.03 298.18

                25.04 298.19

                25.05 298.20

                25.06 298.21

                25.07 298.22

                25.08 298.23

                25.09 298.24

Answer:

Since the force applied at both ends is acting in opposite directions, then the resultant force becomes negative.

= 35 - 25 = 10