Based on the enthalpy changes given for the reactions, which reactions are endothermic?

Answer:

4Al + 3O2 ----> 2Al2O3

Explanation:

first blank 4

second blank 3

third blank 2

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A child sits on a partially filled balloon and decreases the volume by half. What happens to the pressure inside of the balloon?

A. It increases

For the same balloon, how does the density inside the balloon change?

A. increases

A scientist takes a small, partially inflated balloon out of liquid nitrogen (at a very low temperature). As the balloon rests on the table, it begins to grow in size. Which statement(s) best explains why the balloon grows?

B. The air warms and increases particle movement. Increased particle movement leads to increased volume.

C. Increased temperature means increased volume as long as the container is flexible.

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Answer the following questions with or without using a calculator.  

A balloon contains 1.00 mol helium gas at STP. What will the volume of the balloon be if the pressure increases to 2.00 atm?  

✔ 11.2 L

A syringe contains 0.10 mol neon gas at STP. What volume does the syringe indicate?  

✔ 2.24 L

A chemist adds 0.10 mol argon gas to the syringe. The pressure and temperature remain constant. What will be the volume on the syringe after the argon is added?  

✔ 4.48 L

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Acetylene gas (C2H2) reacts with oxygen gas (O2) to produce carbon dioxide (CO2) and water vapor (H2O). How many liters of C2H2 are required to produce 75.0 L of CO2?

37.5  L

What volume of H2O is produced?

37.5  L

What volume of O2 is required?

93.8  L

When making the calculations, did you need to find the number of moles?  

✔ no

Liquid carbon disulfide (CS2) reacts with 44.8 L O2 gas to produce the gases carbon dioxide (CO2) and sulfur dioxide (SO2).  

What is the mass of carbon dioxide produced?

29.3  g

What is the mass of sulfur dioxide produced?

85.4  g

When making the calculations, did you need to find the number of moles?  

✔ yes

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The child is putting pressure on the balloon, and squishing particles together when he/she sits on it, thus increasing pressure. Since particles are being squished closer together, density also increases.

Inflated objects will grow in size when the air inside is hotter. This is because particles move more rapidly. An example would be bike tires being more inflated under hot conditions.

One mole of any gas at standard temperature and pressure (STP) will occupy 22.4 L. If pressure increases, the volume decreases, and vice versa. If moles decreases, so will the volume, and vice versa.

Here are photos of Edge just incase.

The pressure inside of the balloon will Increase. Hence The correct option is (A).

According to this law, the pressure (p) of a given quantity of gas varies inversely with its volume (v) at constant temperature; i.e., in equation form,

pv = k

Where K = constant.

If we consider that temperature of the gas which filled inside the balloon is constant.

We know that , at constant temperature

P₁V₁ = P₂V₂

Given that

V₂ = V₁ / 2

P₂ = P₁V₁/V₂

P₂ = P₁V₁/V₁/2

P₂ = 2P₁

Therefore, the pressure inside the balloon will become double.Hence The correct option is (A).

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Answer:

Because a crystalline solid consists of repeating patterns of its components in three dimensions (a crystal lattice), we can represent the entire crystal by drawing the structure of the smallest identical units that, when stacked together, form the crystal. This basic repeating unit is called a unit cell.Aug 12, 2020

Answer:

the anwser is; B: increasing its speed

Answer:

dont know, will let uk in 2 mins

Explanation:

Explanation:

hope this helps you to understand:)

Answer: The given type of chemical reaction is a double replacement reaction, and each compound has the same set of ions.

Explanation:

When two different compounds chemically react with each other and their ions get exchanged with each other then it leads to the formation of two new compounds. This type of reaction is called double displacement reaction.

For example, [tex]KBr + AgNO_{3} \rightarrow KNO_{3} + AgBr(\downarrow)[/tex]

Here, both KBr and [tex]AgNO_{3}[/tex] are ionic compounds that leads to the formation of two new ionic compounds which are [tex]KNO_{3}[/tex] and AgBr.

Thus, we can conclude that the given type of chemical reaction is a double replacement reaction, and each compound has the same set of ions.

Answer:

Fire is a chemical reaction between oxygen and the fuel. If you want to put out a fire, just get rid of one of those three things – fuel, oxygen or heat. ...It also prevents oxygen from reaching the fuel. Most fire extinguishers work by separating the fuel from the oxygen.

Explanation:

Answer:

It is a chemical change

Explanation:

Answer:

Catalysts allow chemical reactions to occur at temperatures at which the organism lives.

Explanation:

Catalysts are molecules that speeden the rate of chemical reaction by lowering the activation energy of the reaction. In a living system, the catalyst are ENZYMES, which help to hasten up many biochemical reactions.

Another function of catalyst in living systems is that it allows chemical reactions to occur at temperatures at which the organism lives.

Answer:

Explanation:

The pH of a solution can be found by using the formula

[tex]pH = - log [ {H}^{+} ][/tex]

From the question we have

[tex]ph = - log(1.8 \times {10}^{ - 5} ) \\ = 4.7447[/tex]

We have the final answer as

Hope this helps you

Answer:

816L adicionales para mantener la concentración

Explanation:

Cuánta agua debe adicionar el cuidador para que se mantenga la concentración del desinfectante?

El desinfectante, NaClO, idealmente debe estar en una concentración de:

35.8g / 1000L = 0.0358g/L

Como el velador agregó 65g de desinfectante, la cantidad de agua necesaria es:

65g * (1L / 0.0358g) = 1816L de agua son necesarios

Asumiendo que el velador agregó 1000L, el cuidador debe agregar:

1816L - 1000L =

Explanation:

Anything that occupies space and has mass is called matter.

(a) Inter particle space

(b) Inter particle force of attraction

(c) Particle motion

Answer:

chlorine is larger so the symbol is <

Explanation:

Answer:

H2SO4(aq) + MgO(s) → H2O(l) + MgSO4(aq)

Explanation:

We must recall that the oxides of metals are bases. These metal oxides can react with dilute acids to yield salt and water.

Bearing that in mind, we want to obtain magnesium sulfate from a metal oxide and dilute acid.

In this case we need magnesium oxide and dilute sulphuric acid. The reaction occurs as follows;

H2SO4(aq) + MgO(s) → H2O(l) + MgSO4(aq)

Answer:

3.29 M

Explanation:

Molarity refers to the molar concentration of a solution and it can be calculated using the formula below:

Molarity (M) = number of moles (n) ÷ volume (V)

According to this question, the mass of HCl was given to be 60.4 grams and the volume of water as 505 mL.

Using mole = mass/molar mass to convert mass of HCl to moles

Molar mass of HCl = 1.0079 + 35.453 = 36.4609g/mol

mole = 60.4g ÷ 36.4609g/mol

mole = 1.66mol

Volume of water = 505mL = 505/1000 = 0.505L

Molarity, M = 1.66 ÷ 0.505

Molarity of HCl solution = 3.29 M

Answer:

B. Two molecules of pyruvate.

Explanation:

Trust me. I got it RIGHT!

Organic fertilizers are made from mined rock minerals, and natural plant and animal materials. They include ingredients like manure, guano, dried and powdered blood, ground bone, crushed shells, finely pulverized fish, phosphate rock, and wood.

Inorganic fertilizer is synthetic, comprised of minerals and synthetic chemicals. Most of the minerals in inorganic fertilizer are mined from the earth, and balanced inorganic fertilizers are high in all three macronutrients and can contain ammonium sulfate, magnesium sulfate, and potassium chloride.

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Answer: stars vary in their effective temperature and colour. A hot star radiates more energy per second per metre surface area than a cooler star. Does this then mean that a hot star is going to appear brighter to us than a cooler one? The answer to this actually depends on a few factors

Explanation: pa brainiest po

Answer:

72.2 moles of water is spilled

Explanation:

as moles=mass/mr

so mr of water is 16+2=18

13000/18=72.2

for the second one you can work out the moles of o2

by using moles= number of particles /6.02*10^23

so 4.65*10^26/6.02*10^23

so i got 772.4 on my calculator  to work out the amount of mass

u use the equation mass=moles*mr

so 777.2*16=12435g of oxygen gas

hope it helps :)

Answer:

ask someone else I will help later

Answer:

The distilled water will be boiled faster as it does not contain any non - volatile solute.

- The salty water contains different non - volatile salts in it.

- Due to the presence of these salts, its vapour pressure will be decreased and boiling point will be elevated.

- So, salty water will take more time to boil.

- On the other hand, distilled water does not have any such solute and due to this its vapour pressure will not be affected.

- Hence, it will boil fast than salty water.

so dfhhdjdjjfjfjjdjdjdj

Explanation:

Desalination of seawater is considered a renewable source of water, although reducing its dependence on fossil fuel energy is needed for it to be fully renewable.

Answer:

weter

Explanation:

Answer:

The answer is 78.003558.

We assume you are converting between grams Al(OH)3 and mole.

You can view more details on each measurement unit:

molecular weight of Al(OH)3 or mol

This compound is also known as Aluminium Hydroxide.

Explanation:

Answer:

Ver explicación

Explanation:

El método científico se refiere al patrón establecido de resolución de un problema científico. Los siguientes son pasos importantes en el método científico;

Haz una observación.

formular preguntas relevantes.

elabore una hipótesis que pueda ser probada.

Diseña un experimento.

Prueba la hipótesis usando tu diseño experimental.

Teniendo en cuenta ambos escenarios, el último caso en el que estudiantes de diferentes capacidades trabajan juntos para resolver un problema refleja mejor el método científico porque pueden hacerse preguntas entre sí y llegar a hipótesis comprobables que pueden demostrarse como verdaderas o falsas mediante experimentos.

Answer:

acceleration

inversly

opposite

directly

mass

Answer:

Al2(CO3)3. ---heat---> Al2O3 + 3 CO2

Answer:

everything can be found in the picture

Answer:

False

Explanation:

It will occupy 271.7

The first quantum number of a 3p₃ electron in phosphorus 1s2, 2s2, 2p6, 3s2, 3p3 is 3.

Quantum numbers are a set of numbers that describe the position and energy of an electron in an atom.

Principal, azimuthal, magnetic, and spin quantum numbers are the four types of quantum numbers.

Thus, the first quantum number of a 3p₃ electron in phosphorus 1s2, 2s2, 2p6, 3s2, 3p3 is 3.

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Answer:

n=3

Explanation:

i just took the test:)

Answer:

Metals:

1. Metals are strong than non metals

2. Metals can be formed in wires, thin sheets, utensils and any other heavy meachinary for industries.

3. Metals are used for building construction and used in many other manufacturers

Non Metals:

1. Non metals are less stronger than metals.

2. Non metals can be used for manufacturing bottles, toys, bags, files etc.

3. Non metals are used in making of bottles, jars, chairs etc.

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