PLS HELP URGENT
Electron dot diagrams
Use your periodic table to write the electron dot diagrams for the following atoms.
1. Calcium (Ca)
2. Polonium (Po)
3. Moscovium (Mc)
4. Boron (B)
5. Fluorine (F)

Answer:

85.6

Explanation:

(72 x 85) + (28 x 87)

-----------------------------

        100

= 85.56

= 85.6 (3 s.f.)

Answer:

hydrochloric acid

Explanation:

The concept of significant figures are mainly used by scientist and engineer to know the significance of digits in a measurement. Therefore, 3,545,530 upto 3 significant figures is 3.54 x 10³.

Significant figures are the figures that indicate the degree of accuracy of a value. It tells about the precision of a value. It gives an idea about the digits that are necessary to indicate the experimental value.

Rules for counting significant figures are:

Number between 1 to 9 is always significant

Zeroes after a number has got no significance

Zeroes before a number has got no significance

Zeroes between number has got significance

3,545,530 upto 3 significant figures is 3.54 x 10³.

Therefore, 3,545,530 upto 3 significant figures is 3.54 x 10³.

To learn more about Significant figures, here:

https://brainly.com/question/12656148?

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Answer:

143.9946 g

Explanation:

Answer:

true

Explanation:

Answer:

Turgor pressure in plants. Turgor pressure within cells is regulated by osmosis and this also causes the cell wall to expand during growth.

Explanation:

I hope that helps

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:

sorry if this is wrong but B

Explanation:

ITS C

Oxygen, APT, and Glucose

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

Explanation:

Answer:

a)82.5 g

Explanation:

To solve this problem we will use Avogadro's number, which states the number of formula units per mole.

Then we convert 1.41 moles of NaCl to grams, using its molar mass:

The closest answer is option a).

Answer:

C

Explanation:

No change.

The total number moles of products = The Total number of reactants

Answer:

Silicon tetrachloride

Explanation:

Answer:

C. Decomposition of potassium permanganate(Heating)

Explanation:

The equation of the reaction is given as;

2KMnO4 -> K2MnO4 + MnO2(s)  + O2(g)

Reactant = 2KMnO4

Products = K2MnO4 + MnO2(s)  + O2(g)

A. Oxygen turned in to carbon dioxide

Incorrect option - Oxygen is not the reactant

B. Sulphate and lithium boiled

Incorrect option -  Sulphate and lithium are not part of this reaction

C. Decomposition of potassium permanganate(Heating)

Correct option - potassium permanganate decomposed to form K2MnO4 + MnO2(s)  + O2(g)

D. None of the above

Incorrect option

Answer  :32,5 g NaCl equal 0,556 moles.

Explanation:

Answer:

Limiting reactant: O2

grams NO2 produced = 230.276 g NO2

grams of NO unused = 26.67 gNO

Explanation:

2NO + O2 --> 2NO2

Step 1: Determine the molar ratio NO:O2

molar ratio NO:O2 = 5.895: 2.503 = 2.35

stoichiometric molar ratio NO:O2 = 2:1

So, O2 is the limiting reactant.

Step2: Determine the grams of NO2:

?g NO2 = moles O2 x (2moles NO2/1 mol O2) x (MM NO2/ 1 mol NO2) = 2.503 x 2 x 46 = 230.276 g NO2

Step 3: Determine the amount of excess reagent unreacted

moles excess NO reacted = moles O2 x (2 moles NO/1 mol O2) = 2.503 x 2 = 5.006 moles NO reacted

moles NO unreacted = total moles NO - moles NO reacted = 5.895-5.006 =0.889 moles NO unreacted

mass NO unreacted = moles NO unreacted x MM NO = 0.889 x 30 =26.67 g NO unreacted

Answer:

0.017 moles of ammonia remains after the reaction is stopped.

Explanation:

The reaction is:

4NH₃  +  5O₂  →  4NO  +  6H₂O

The first step is to convert the mass to moles, of each reactant:

2 g .  1mol/ 17g = 0.117 moles of NH₃

4 g . 1mol /32g = 0.125 moles of O₂

Ammonia, states the question, is the excess reactant so we can confirm it,

5 moles of oxygen need 4 moles of ammonia to react (by stoichiometry)

Then, 0.125 moles of oxygen may react to (0.125 . 4) / 5 = 0.1 moles

As we have 0.117 moles of ammonia and we need 0.1 moles.

(0.117 - 0.1) = 0.017 moles remains after the reaction is completed.

If we convert the moles to mass we have:

0.017 mol . 17 g /1mol = 0.289 g

Answer:

The formation of a gas is a clue to chemical changes. The bubbles of gas that you observed form when an antacid is dropped into water is an example of change. Another clue that a chemical change has occurred is the formation of a solid.

Explanation:

Explanation:

➢number of moles. Moles and Chemical Reactions. Chapter 4. 3 H2. + N2. →. 2 NH3 ... How many grams of NH3 would form if 2.11 moles of N2 reacted with ...

In science, literature, and everything, equilibrium has the same meaning. The meaning simply put, is balance. If you wanted a sentence example, it could be something like:

'He sat down to try and recover his equilibrium.'

Or

'They can't maintain enough equilibrium to ride a bike.'

I hope you understand the meaning now?

Answer:

60 Liters

Explanation:

The equation for this reaction is given as;

N2 + 3H2 → 2NH3  

From the reaction;

3 mol of H2 produces 2 mol of NH3

At STP;

1 mol = 22.4 L

This means

67.2 L ( 3 * 22.4) of H2 produces 44.8 L ( 2 * 22.4) of NH3

How many L of H2 would produce 40 L of NH3

67.2 = 44.8

x = 40

Solving for x;

x = 40 * 67.2 / 44.8

x = 60 L

Answer:

True

Explanation:

The reason why is because frost is a result of a chemical reaction

Answer:

I hope this will help you

Explanation:

The air that is inside a ship is much less dense than water. That's what keeps it floating! The average density of the total volume of the ship and everything inside of it (including the air) must be less than the same volume of water.

Please make me brilliant

Explanation:

It to be fossilized, the remains usually to be covered by sediment soon after death. sediment can include the sandy seafloor,lava,and even sticky tar. Over time, minerals in the sediment seep in to remains. The remains become fossilized.

Answer:chemical markers

Explanation:

I’m smart give brainlest plz

Answer:

2. for number two I asks what the experiment is showing, I need the picture of the experiment.

3.  As temperature increases, the particles will gain kinetic energy causing it to move more rapidly and randomly. However, this causes the gas to expand as the particles will have more energy to roam freely. as temperature increases, Volume increases.

4.  Im not sure D: