What action is the best example of a direct observation

Answer:

334.2× 10²³ molecules

Explanation:

Given data:

Mass of water = 1 Kg ( 1000 g )

Number of molecules = ?

Solution:

Number of moles of water:

Number of moles = mass/ molar mass

Number of moles = 1000 g/ 18 g/mol

Number of moles = 55.5 mol

1 mole contain 6.022× 10²³ molecules

55.5 mol×6.022× 10²³ molecules

334.2× 10²³ molecules

Answer:

2 A): Fluorine

B): more protons, more force attraction less atomic radius

3A): Helium

B):it has small atomic radius

4 th question is not visible.....

Photosynthesis is a chemical change as:

A. New substances are formed with properties that are different from the original substances.

A chemical change happens when one chemical substance is transformed into one or more different substances. A chemical change is different from a physical change, which doesn't rearrange atoms or molecules and produce a completely new substance.

Thus, correct option is A which proves that photosynthesis is a chemical change.

Find more information about Chemical change here: brainly.com/question/453535

Answer:

Yes

Explanation:

Remember, Newton's third law of motion; which says in part that "Every action has an equal and opposite reaction."

Hence, in this case, the fact that the doorbell rang out implies that there was another force that was exerted on it; which is, John's finger pressing the doorbell.

In other words, when John uses his fingers to press the doorbell button he applies a force (a mechanical force), and that force results in an opposite reaction; the ringing of the doorbell.

Answer:

conclusion.

Explanation:

Answer:

how am i suppose to put it in largest to smallest if u didnt give any numbers

Answer:

V = 2.75 L

Explanation:

Given that,

Mass of liquid glycerol, m = 3470 g

The density of liquid glycerol, d = 1.26 g/cm³

We need to find the volume of liquid glycerol.

We know that,

Density=mass/volume

[tex]V=\dfrac{m}{d}\\\\V=\dfrac{3470\ g}{1.26\ g/cm^3}\\\\V=2753.96\ cm^3[/tex]

We know that, 1 cm³ = 0.001 L

V = 2.75 L

So, the volume of liquid glycerol is 2.75 L.

Answer:

V₂ = 30.20 L

Explanation:

Given data:

Initial volume = 45 L

Initial temperature = 298 K

Final temperature = 200 K

Final volume = ?

Solution;

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume  

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

V₂ = V₁T₂/T₁  

V₂ = 45 L × 200 K / 298 k

V₂ = 9000 L.K / 298 K

V₂ = 30.20 L

Answer:

I think the last one

Explanation:

The reason for that is because when you go up to present something you always want to try to hav believability and confidence.

Answer:

believability and confidence

Explanation:

Answer:

Erythrocytes

Erythrocytes do not contain a nucleus. This would make answer choice "A" correct. Erythrocytes are red blood cells and these cells differ from the other cells of the body because of the absence of the nucleus. All the other cells noted have nuclei.

Explanation:

Have A Wonderful Day !!

Answer:a. Prokaryotes

Explanation:

Answer:

F=ma

=(0.3kg) (50m/s/s)

F =15 kg per m/s/s

Answer:

Explanation:

What is this?

Answer:

100 degrees Celsius

Explanation:

If  you look at the to number lines you want to find 212 degrees Fahrenheit on the bottom line then look at the top number line where the 212 lines up which is 100 degrees Celsius.

Answer: Positive- Protons

Negative- Electrons

Explanation:

Answer:

radioactive

nonmetal

hydrogen

liquid

rarely (since they have a full valence electron shell)

inner transition

Answer:

Subatomic particles

Explanation:

I hope it helped

Answer:

Because 60 percent of our body weight is made up of water. Our bodies use water in all the cells, organs, and tissues, to help regulate body temperature and maintain other bodily functions.

Explanation:

Our bodies is made out of 60% water and even if the percentage goes down 1% we could faint. 5% and we could die. We wash off with water to clean ourselves. We use water to cook like boiling pasta. Water is a necessity not just humans need it but plants need it to grow and germinate. Hope this helps sorry it took so long. I had a fight with autocorrect.

Answer:

Nitrogen group element, any of the chemical elements that constitute Group 15 (Va) of the periodic table. The group consists of nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), and moscovium (Mc)

Explanation:

electric energy to heat and light energy

Answer:

Decrease the temperature

Explanation:

If you increase the temperature the vapor pressure will increase. Adding more liquid to the container is completely irrelevant.

Decreasing the temperature would reduce the vapor pressure of a sealed container of liquid. Therefore, option (C) is correct.

Vapour pressure is the pressure that the vapour phase puts on the liquid phase when the two phases are in balance. At higher temperatures, the molecules of the liquid have more energy and are more likely to move into the vapour phase. This makes the vapour pressure go up.

But when the temperature goes down, the average energy of the molecules in the liquid goes down, which slows the rate of evaporation. This means that fewer molecules are moving from the liquid phase to the vapour phase. As a result, the vapour pressure is lower.

Putting more liquid in the bottle wouldn't change the vapour pressure directly. The temperature and the type of liquid, not the amount, are what decide the vapor pressure.

Learn more about Vapor Pressure, here:

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Answer: F. both c and d

Explanation:

homogeneous mixture is of same kind/phase. so the most appropriate answer we can take is smoothie and white bread dough :)

Answer:

the answer is

a

b

d

c

Explanation:

hopeit help

The correct matches will be:

                     [tex][Cl]=1s^22s^22p^63s^23p^5[/tex]

                     [tex][Ne]=1s^22s^22p^6[/tex]

                       [tex][P]=1s^22s^22p^63s^23p^3[/tex]

                        [tex][S]=1s^22s^22p^63s^23p^4[/tex]

So, from this, we can conclude that the correct matches will be:

Learn more about the valence electrons here:

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Answer:  p = m/Vp = 39.5 g/5.0 cm3p = 7.9 g/cm3 4.

Answer:

B.

Explanation:

Explanation:

To calculate the number of atoms in a sample, divide its weight in grams by the amu atomic mass from the periodic table, then multiply the result by Avogadro's number: 6.02 x 10^23.

220 g H₂O

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Stoichiometry

Step 1: Define

12 moles H₂O (water)

Step 2: Identify Conversions

Molar Mass of H - 1.01 g/mol

Molar Mass of O - 16.00 g/mol

Molar Mass of H₂O - 2(1.01) + 16.00 = 18.02 g/mol

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 2 sig figs.

216.24 g H₂O ≈ 220 g H₂O

Answer:

Explanation:

Atoms consist of three basic particles: protons, electrons, and neutrons. The nucleus (center) of the atom contains the protons (positively charged) and the neutrons (no charge). The outermost regions of the atom are called electron shells and contain the electrons (negatively charged).