What percent of I-125 has decayed if there are 37.5g of the original sample left?

Answer:

Buffalo and Watertown.

Explanation:

This is correct as the Interior lowlands are located ib the US. These are correct as the others are in the US but aren't located anywhere near the Interior Lowlands.

Answer:

As Naphthalene undergoes sublimation, we use sublimation process. On condensing naphthalene can be separated.

Answer:

H₂O₂

Explanation:

Hydrogen peroxide is a typical example of a compound molecule. A compound is made up of one or more atoms that are combined together in a definite grouping.

The properties of a compound is different from those of the elements that combines to from them.

Answer:

d = 8.96 g/cm³

Explanation:

Given data:

Volume of sample = 10.0 cm³

Mass of copper = 89.6 g

Density of copper = ?

Solution:

Formula:

d = m/v

d = density

m = mass

v = volume

by putting values,

d = 89.6 g/ 10.0 cm³

d = 8.96 g/cm³

Answer:

159571 lb or cubic feet

Explanation:

Answer:

4 mol

Explanation:

Given data:

Number of atoms of He = 2.4 × 10²⁴ atoms

Number of moles of He = ?

Solution:

Avogadro number:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ atoms

2.4 × 10²⁴ atoms × 1mol / 6.022 × 10²³ atoms

0.398× 10¹ mol

3.98 mol ≅ 4 mol

Explanation:

In animal cells, vacuoles are small and help sequester waste products. In plant cells, vacuoles help maintain water balance. Therefore the answer should be B. For Storage

Hope this helps!

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Answer:

Mass = 917.4 g

Explanation:

Given data:

Number of molecules = 3.00 ×10²⁴ molecules

Mass in gram = ?

Solution:

1 mole contain 6.022 × 10²³ molecules

3.00 ×10²⁴ molecules × 1 mol /  6.022 × 10²³ molecules

0.5×10¹ mol

5 mol

Mass in gram:

Mass = number of moles  × molar mass

Mass = 5 mol  × 183.48 g/mol

Mass = 917.4 g

Answer:

Between carbon and silicon, silicon element has the strongest attraction between its nucleus and its valence electrons.

because silicon's nucleus is bigger than carbon.silicon loses electrons easily than carbon.

Answer: [tex]KClO_3[/tex] is the limiting reactant in the given reaction.

Explanation:

Limiting reagent is defined as the chemical specie which gets totally consumed in the reaction and the formation of product is dependent on this reagent.

We are given:

Moles of [tex]P_4[/tex] = 30 moles

Moles of [tex]KClO_3[/tex] = 86 moles

The given chemical equation follows:

[tex]10KCIO_3+3P_4\rightarrow 3P_4O_{10}+10KCI[/tex]

By Stoichiometry of the reaction:

If 10 moles of [tex]KClO_3[/tex] reacts with 3 moles of [tex]P_4[/tex]

Then, 86 moles of [tex]KClO_3[/tex] will react with = [tex]\frac{3}{10}\times 86=25.8moles[/tex] of [tex]P_4[/tex]

As, given amount of [tex]P_4[/tex] is more than the required amount. So, it is considered as an excess reagent.

Therefore, [tex]KClO_3[/tex] is considered as a limiting reactant because it limits the formation of product.

Answer:

D.) This atom has an atomic number of 50

Explanation:

A is wrong because we determine the type of atom by their number of protons, not the number of neutrons. This makes the atom Tin (Sn).

B is wrong because both protons and neutrons contribute to the weight of an atom, not just neutrons

C is wrong because the correct name for this isotope would be tin-119, which is calculated by adding the protons and neutrons

D is correct because isotopes of the same element always share the same atomic number

Explanation:

alto cumulus is the pic

Answer:

2.8g/cm³

Explanation:

Given parameters:

Mass of cube = 42g

Volume of cube  = 15cm³

Unknown:

Density of the cube  = ?

Solution:

Density is defined as the mass per unit volume of a substance. It is mathematically expressed as:

 Density  = [tex]\frac{mass}{volume}[/tex]  

So;

 Density  = [tex]\frac{42}{15}[/tex]   = 2.8g/cm³

Answer:

[OH⁻] = 3.34x10⁻³M; Percent ionization = 0.54%; pH = 11.52

Explanation:

Kb of the reaction:

NH3 + H2O(l) ⇄ NH4+ + OH-

Is:

Kb = 1.8x10⁻⁵ = [NH₄⁺] [OH⁻] / [NH₃]

As all NH₄⁺ and OH⁻ comes from the same source we can write:

[NH₄⁺] = [OH⁻] = X

And as [NH₃] = 0.619M

1.8x10⁻⁵ = [X] [X] / [0.619M]

1.11x10⁻⁵ = X²

3.34x10⁻³ = X = [NH₄⁺] = [OH⁻]

% ionization:

[NH₄⁺] / [NH₃] * 100 = 3.34x10⁻³M / 0.619M * 100 = 0.54%

pH:

As pOH = -log [OH-]

pOH = 2.48

pH = 14 - pOH

Answer:

Sound is vibrations that travel through a medium, and which are then converted into electrical signals by our brain so that we interpret them as a noise that we hear. These vibrations consist of particles colliding with each other (this is why sound cannot travel through space; there are no particles). At warmer temperatures, the particles that make up air will move faster, so these collisions will happen more frequently. Therefore the vibrations occur more quickly, so sound travels faster and reaches our ears in a shorter amount of time.

The speed of sound can travel faster in hot air than it can in cold air. This is because the molecules of air can move even faster and the vibrations of the sound wave can transmit faster. Sound is a type of mechanical wave, meaning that it requires a medium to transmit energy. Mediums are any substance that has mass and takes up space, from the air in the room to the metal atoms in an iron fence.

Explanation:

hope that helps :)

Answer:

Sound travels faster in a warm room because temperature affects the speed of a wave. In a warm room, the particles of air move faster and have higher chances of bumping into each other, which then increases the instances of energy transfer.

Explanation:

just trust me cuz

Answer:

imma go with the answer B

The product in the reaction  [tex]\rm Zn + 2HCl \rightarrow[/tex] is [tex]\rm ZnCl_2 + H_2[/tex]. The correct answer is option D.

A reaction is a process that involves the transformation of one or more substances into one or more different substances.

The reaction between zinc (Zn) and hydrochloric acid (HCl) is a classic example of a single displacement reaction. In this reaction, zinc reacts with hydrochloric acid to produce zinc chloride ([tex]\rm ZnCl_2[/tex]) and hydrogen gas ([tex]\rm H_2[/tex]).

The balanced chemical equation for this reaction is:

[tex]\rm Zn(s) + 2HCl(aq) \rightarrow ZnCl_2(aq) + H_2(g)[/tex]

Therefore, the product of the reaction between zinc and hydrochloric acid is zinc chloride ([tex]\rm ZnCl_2[/tex]) and hydrogen gas ([tex]\rm H_2[/tex]). Option D is the correct answer.

Learn more about reaction here:

https://brainly.com/question/16737295

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Answer:

Diaphragm controls the amount of light reaching the specimen. It is located above the condenser and below the stage. Most high quality microscopes include an Abbe condenser with an iris diaphragm. Combined, they control both the focus and quantity of light applied to the specimen.

Answer:

0.55g/L

Explanation:

Given parameters;

Mass of salt  = 55g

Volume of water  = 100L

Unknown:

g/L concentration  = ?

Solution:

To solve this problem, we must understand that concentration is the amount of solute per solution

 g/L concentration  = [tex]\frac{55}{100}[/tex]   = 0.55g/L

Answer:

I'd say about 8?

Explanation:

if you wanna make them huge make about 6

Answer:

Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.

Explanation:

Polar molecules occur when there is an electronegativity difference between the bonded atoms. Nonpolar molecules occur when electrons are shared equal between atoms of a diatomic molecule or when polar bonds in a larger molecule cancel each other out.

Answer:

I think it would be Yellow

Answer:

0.4 km/h  velocity is also the direction their going, in this case the person, that I'll name billy bob joe, is going in so yeh

Explanation:

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Answer:

An ideal gas is a theoretical concept and a real gas behaves in an ideal manner under conditions which includes a high temperature and a low pressure such that the gas has high kinetic energy, and the intermolecular forces between the molecules are weak

The Ideal Gas Law is P·V = n·R·T

Where;

P = The pressure of the gas

V = The volume of the gas

n = The number of moles of the gas

R = The Universal Gas Constant

T = The temperature of the gas

For a gas cooled to 10 Kelvin and placed under high pressure, the interaction between individual gas molecules increases, and the kinetic energy of the gases is much lower and more comparable to the inter molecular forces between the gas molecules, which in turn produces observable changes from the initial ideal behavior of the gas such that the gas behavior deviates from the Ideal Gas Laws appreciably and are better modelled by the Van der Waals Equations which takes into account, the volume the gas particles occupy and the intermolecular forces between the molecules

The Van der Waals equation is presented as follows;

[tex]P = \dfrac{R \cdot T}{V - b} - \dfrac{a}{V^2}[/tex]

Where;

V = The molar volume

a = The gas constant a represents the attractive forces between the gas particles

b = Represent the volume occupied by the particles of the gas

Explanation:

Answer: A, B, & C

Explanation:

A. The ideal gas model assumes that gas particles experience no intermolecular attractions and these forces cause the gas to deviate from ideal behavior.

B. At very low temperatures, gas particles move slowly.

C. At very high pressures, gas particles are very close together.

Got it right on edge :)

Answer:

by focal length of the eyepiece.

Explanation:

hope it helps!!plz mark as brainleist.

Answer:

it would become darker. there would be a higher level of water pressure. and there would be less animals, or different alimals.

Answer:

3.79 x 10²⁴atoms

Explanation:

Given parameters:

Number moles of lead  = 6.3moles

Unknown:

Number of atoms  = ?

Solution:

To solve this problem,

              1 mole of a substance contains  6.02 x 10²³ atoms

            6.3 mole of Pb  will contain 6.3  x 6.02 x 10²³ = 3.79 x 10²⁴atoms

Answer:

fire

Explanation:

Answer:

ants if you splash a ant with sum water that shít is dead