Please help me on this exsam question ASAP!!! Please

Answer:    D

Explanation:

Trust me please

Answer:

For example, when water solutions of calcium nitrate and sodium carbonate are mixed, calcium carbonate precipitates from the solution while the other product, sodium nitrate, remains dissolved. It is a precipitate.

Explanation:

Answer:

Dependant

Explanation:

Depending on the kind of substance you have (since ur answer of what substances was vauge) you would want to look at the molecular structure of the substances.

Understanding intermolecular bonds are key here (research this)

For example, Bromine is found as Br2 and only exerts London dispersion forces as there is no difference in polarity. And because this force is weaker, it has a lower boiling point

Another example being something like Hydrochloric acid (HCl). This is where Hydrogen acts as the positive atom while chlorine is the negative atom. This creates a stronger force and thus, a higher boiling point than Br2

Finally, there is Something like H2O where the force in play is Hydrogen bonding as Nitrogen, Oxygen, Fluorine where the bonds are strongest due to the electronegativity is at the greatest difference between these and Hydrogen. and thus having a higher boiling point.

So depending on the substance's bond, that will help determine the boiling point. If they fall under the same group, go based on the greatest difference in electronegativity.

I don't know if this is what you're looking for but, hope this helps. :)

Answer:

13. A

14. C

Explanation: i tried my best

Answer:

SO₄⁻² (aq)  +  Mg²⁺ (aq)  ⇄  MgSO₄ (s) ↓

Precipitation reaction

Explanation:

Mg²⁻ is one of the metals at group 2 in the Perodic Table. This group is called, the alkaline earth metals.

To make precipitate the Mg²⁺ we can use a salt of sulfate, either flouride or phosphate. Those are three salts that can precipitate this metal.

We use sodium as cathion so, first of all we dissociate them:

Na₂SO₄ (aq) →  2Na⁺  (aq)  +  SO₄⁻² (aq)

NaF (aq) →  Na⁺ (aq) +  F⁻ (aq)

Na₃PO₄ (aq) →  3Na⁺ (aq)  +  PO₄⁻³ (aq)

In all cases, the reaction is of the precipitation type and is conditioned by the Kps, the solubility product constant. Let's bond the anions with Mg²⁺.

SO₄⁻² (aq)  +  Mg²⁺ (aq)  ⇄  MgSO₄ (s) ↓    Kps

2F⁻ (aq)  +  Mg²⁺ (aq)  ⇄   MgF₂ (s) ↓      Kps

2PO₄⁻³ (aq)  +  3Mg²⁺ (aq)  ⇄  Mg₃PO₄ (s) ↓   Kps  

Answer:

like what happens In 3 hours

With high cholesterol, you can develop fatty deposits in your blood vessels. Eventually, these deposits grow, making it difficult for enough blood to flow through your arteries. Sometimes, those deposits can break suddenly and form a clot that causes a heart attack or stroke.

Answer:

Cholesterol is a waxy substance found in your blood. Your body needs cholesterol to build healthy cells, but high levels of cholesterol can increase your risk of heart disease.

With high cholesterol, you can develop fatty deposits in your blood vessels. Eventually, these deposits grow, making it difficult for enough blood to flow through your arteries. Sometimes, those deposits can break suddenly and form a clot that causes a heart attack or stroke.

Explanation:

High cholesterol can cause a dangerous accumulation of cholesterol and other deposits on the walls of your arteries (atherosclerosis). These deposits (plaques) can reduce blood flow through your arteries, which can cause complications, such as:

Chest pain. If the arteries that supply your heart with blood (coronary arteries) are affected, you might have chest pain (angina) and other symptoms of coronary artery disease.

Heart attack. If plaques tear or rupture, a blood clot can form at the plaque-rupture site — blocking the flow of blood or breaking free and plugging an artery downstream. If blood flow to part of your heart stops, you'll have a heart attack.

Stroke. Similar to a heart attack, a stroke occurs when a blood clot blocks blood flow to part of your brain.

Answer:

0.1 m

djdjdncncnvkvvvp

Answer:

the answer is this hope it helps

Answer:

a. [tex]r_{N_2O_5}=-0.075M/min[/tex]

b. [tex]r_{N_2O_4}=0.075M/min[/tex]

Explanation:

Hello.

In this case, according to the balanced chemical reaction, we can write the law of rate proportions:

[tex]\frac{r_{N_2O_5}}{-2} =\frac{r_{N_2O_4}}{2} =\frac{r_{O_2}}{1}[/tex]

Thus, we proceed as follows:

a. Since the rate of oxygen production is 0.15 M/min, we can make the following setup:

[tex]\frac{r_{N_2O_5}}{-2} =\frac{r_{O_2}}{1}\\\\r_{N_2O_5}=\frac{r_{O_2}}{-2} =\frac{0.15M/min}{-2}\\\\ r_{N_2O_5}=-0.075M/min[/tex]

b. Since the rate of oxygen production is 0.15 M/min, we can make the following setup:

[tex]\frac{r_{N_2O_4}}{2} =\frac{r_{O_2}}{1}\\\\r_{N_2O_4}=\frac{r_{O_2}}{2} =\frac{0.15M/min}{2}\\\\ r_{N_2O_4}=0.075M/min[/tex]

Best regards!

The balanced equation:

N2 + 3 F2 ---> 2 NF3

Answer:

You didn't provide any options but from this, choose the answer in your options.

DNA has a double helix structure. It creates an extremely thin spiral that can not be seen to the naked human eye. It contains sugar and phosphate molecules. The spiral contains colored nitrogenous bases.

Answer:

Can u somehow make it bigger please?

Explanation:

Answer: because its more scientific and "formal"? I guess.

Explanation:

Answer:

because it is so fundamental to our world . chemistry plays a role in everyone lives.

It touches almost every aspect of our existence in some way.

Chemistry is essential for meeting our basic needs of food, cloth, etc.

Chemistry plays a important and useful role towards the development and growth of industries.

chemistry also helps you become who you want to be.

Answer:

373 K; 253 K

0°C ; -258°C

Explanation:

In order to change Temperatures to Absolute Value (Kelvin) you shoud do this sum:

T° in C  + 273 = T° in K

For question 1:

100°C + 273 = 373K

-20°C + 273 = 253K

For question 2:

T° K - 273 = T° C

273 K - 273 = 0°C

15 k + 273 = -258 °C

Answer:

-67.8

Explanation:

Answer:

0.119 moles

Explanation:

molar mass of Fe = 55.845g

to find moles = mass/ molar mass

so moles of Fe = 20/55.845

= 0.358 moles

for the equation you are given

for every three Fe, it produces 1 Fe3O4 , meaning the ratio is 3:1

if you have 0.358 moles of Fe, that means the number of moles of Fe3O4  will equal to one third of that,

thus

moles of Fe3O4 = 1/3 x 0.358 = 0.119

Answer:

2.) When waves hit the shoreline, they transfer their energy to the land.

3.) Wind transfers its energy to the water to create ocean waves.

Explanation:

I got it right on the test.

Wind transfers its energy to the water of the ocean to produce waves and this waves transfers its energy to the land.

Transfer of energy means the relocation of energy from one system to another or from one form to other.

When wind flows over the surface of the ocean, then they transfer their energy to water of the ocean. This absorbed energy by the water of ocean is seen in the form of the ocean waves or also known as wave energy.

Now the vertical motion of this waves on the surface of the ocean due to the presence of the kinetic energy, transfers its energy to the sea shoreline and results in the displacement of the sand or land.

Hence, option (2) & (3) is correct i.e. wind transfers its energy to the water and waves transfers its energy to the land.

To know more about transfer of energy, visit below link:

https://brainly.com/question/2667612

Answer:

Chemistry has a reputation for being a complicated and boring science, but for the most part, that reputation is undeserved. Fireworks and explosions are based on chemistry, so it's definitely not a boring science. If you take classes in chemistry, you'll apply math and logic, which can make studying chemistry a challenge if you are weak in those areas. However, anyone can understand the basics of how things work, and that's the study of chemistry. In a nutshell, the importance of chemistry is that it explains the world around you.

Chemistry Explained

Cooking: Chemistry explains how food changes as you cook it, how it rots, how to preserve food, how your body uses the food you eat, and how ingredients interact to make food.

Cleaning: Part of the importance of chemistry is it explains how cleaning works. You use chemistry to help decide what cleaner is best for dishes, laundry, yourself, and your home. You use chemistry when you use bleaches and disinfectants, even ordinary soap and water. How do they work? That's chemistry.

Medicine: You need to understand basic chemistry so you can understand how vitamins, supplements, and drugs can help or harm you. Part of the importance of chemistry lies in developing and testing new medical treatments and medicines.

Environmental Issues: Chemistry is at the heart of environmental issues. What makes one chemical a nutrient and another chemical a pollutant? How can you clean up the environment? What processes can produce the things you need without harming the environment?

We humans are all chemists. We use chemicals every day and perform chemical reactions without thinking much about them. Chemistry is important because everything you do is chemistry! Even your body is made of chemicals. Chemical reactions occur when you breathe, eat, or just sit there reading. All matter is made of chemicals, so the importance of chemistry is that it's the study of everything.

Importance of Taking Chemistry

Everyone can and should understand basic chemistry, but it may be important for you to take a course in chemistry or even make a career out of it. It's important to understand chemistry if you are studying any of the sciences because all of the sciences involve matter and the interactions between types of matter.

Students wanting to become doctors, nurses, physicists, nutritionists, geologists, pharmacists, and (of course) chemists all study chemistry. You might want to make a career out of chemistry because chemistry-related jobs are plentiful and high-paying. The importance of chemistry won't be diminished over time, so it will remain a promising career path.

Paragraph 1:

Chemistry is important Because it is so fundamental to our world, chemistry plays a role in everyone's lives and touches almost every aspect of our existence in some way.

Paragraph 2:

Chemistry is essential for meeting our basic needs of food, clothing, shelter, health, energy, and clean air, water, and soil.

Paragraph 3:

Even your body is made of chemicals. Chemical reactions occur when you breathe, eat, or just sit there reading. All matter is made of chemicals, so the importance of chemistry is that it's the study of everything.

Paragraph 4:

Chemistry has a reputation for being a complicated and boring science, but for the most part, that reputation is undeserved.

Paragraph 5:

Fireworks and explosions are based on chemistry, so it's definitely not a boring science. If you take classes in chemistry, you'll apply math and logic, which can make studying chemistry a challenge if you are weak in those areas.

Hope it helps :))

Answer:

I hope it's help uu

if wrong then sry

Answer;

They indicate the acidity level. That is, the less pH, the more acidic

Hope it helps :)

Answer:

The reason why Newtons first law of motion is sometimes called the law of inertia is because it states that if the object is in motion, it will not rest unless an unbalanced force acts on the object.

More reactants have more atoms to react to form more products.

More reactants have more atoms to react to form more products in a chemical reaction.

This is the process which involves two or more molecules known as reactants collide with the right orientation and force to form a new product.

Increase in reactants means presence of more molecules involved in the reaction thereby leading to the formation of more product.

Read more about Chemical reaction here https://brainly.com/question/11231920?source=archive