Which is an example of a chemical change?
A.
freezing water
B.
boiling water
C.
baking a cake
D.
felling a tree
E.
breaking a glass pane

2Mg(s)+O₂(g)⇒2MgO(s)

Equalization of chemical reactions can be done using variables. Steps in equalizing the reaction equation:

1. gives a coefficient on substances involved in the equation of reaction such as a, b, or c, etc.

2. make an equation based on the similarity of the number of atoms where the number of atoms = coefficient × index (subscript) between reactant and product

3. Select the coefficient of the substance with the most complex chemical formula equal to 1

Reaction(syntesis / combination)

Mg(s)+O₂(g)⇒MgO(s)

give coefficient

aMg(s)+bO₂(g)⇒MgO(s)

Mg, left=a, right 1⇒a=1

O,left=2b,right 1⇒2b=1,b=0.5

Mg(s)+0.5O₂(g)⇒MgO(s) x 2

2Mg(s)+O₂(g)⇒2MgO(s)

Explanation:

A single covalent bond is made up of 2 electrons (one from each atom). It is represented with a single line.

Each line is represented as one dot and one cross (. x)

A double covalent bond is made up of 4 electrons (2 from each atom). It is represented using 2 lines. As dot and cross, it will be represented with 2 dots and 2 crosses.

A triple covalent bond is made up of 6 electrons (3 from each atom). It is represented using 3 lines. As dot and cross, it will be represented with 3 dots and 3 crosses.

Know the number of electron (s) needed by the atom to have noble gas configuration / stable (Key: You should know your electron arrangement / group number / Refer to table provided)*.

Groups and the number of electrons needed for atoms to have noble gas configuration or have full outer shell(s).

Group 4: Four (4) electrons needed for the outer shell to become full / noble gas configuration;

Group 5: Three (3) electrons needed by the atom to have a full outer shell / noble gas configuration;

Group 6: Two (2) electrons needed

Group 7: One (1) electron needed

Answer:

Na

Explanation:

On the periodic table, the atomic radius of an atom typically decreases when going from left to right and increases when going from top to bottom.

Answer:

i dont get your question Man

In mathematics, a set is a well-defined collection of distinct objects

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Answer:B

Explanation:

Answer:

E. ^51 V

Atomic number (number of protons in the nucleus): 23

Atomic symbol (on the periodic table of the elements): V

Atomic weight (average mass of the atom): 50.9415

Density: grams per cubic centimeter

Phase at room temperature: Solid

Melting point: 3,470 degrees Fahrenheit (1,910 degrees Celsius)

Boiling point: 6,165 F (3,407 C)

Number of isotopes (atoms of the same element with a different number of neutrons): 2; one stable V-51; one radioactive V-50

Most common isotopes: V-51 (99.75 percent natural abundance)

Answer:

Explanation:This unequal distribution of electrons is known as a polar covalent bond, characterized by a partial positive charge on one atom and a partial negative charge on the other. The atom that attracts the electrons more strongly acquires the partial negative charge and vice versa.

Answer:

C . 24 L

Explanation:

Given data:

Initial volume of gas = 20.0 L

Initial pressure of gas = 660 mmHg

Final volume = ?

Final pressure = 550 mmHg

Solution:

The given problem will be solved through the Boly's law,

"The volume of given amount of gas is inversely proportional to its pressure by keeping the temperature and number of moles constant"

Mathematical expression:

P₁V₁ = P₂V₂

P₁ = Initial pressure

V₁ = initial volume

P₂ = final pressure

V₂ = final volume  

Now we will put the values in formula,

P₁V₁ = P₂V₂

660 mmHg × 20.0 L = 550 mmHg × V₂

V₂ = 13200 mmHg. L/ 550 mmHg

V₂ = 24 L

Answer:

Na2O

explanation.

Ionic bonds refers to complete transfer of electrons from one atom to another

Ionic Bonding (the transfer of valence electrons)

Answer:

Ok:

Explanation:

Sodium gives fluorine an electron. This is in part due to electronegativity differences because sodium likes to lose an electron and fluorine likes to gain. As a result, sodium and become positively charged and fluorine negatively charged. This will for electrostatic attraction and the sodium and fluorine will form a bond. This bond is called an ionic bond.

Answer:

Explanation:

Ba( OH)₂ + 2HCl = BaCl₂ + 2H₂O .

75.5 mL of 0.247 M barium hydroxide = .0755  x .247 = .01864 moles

95.0 mL of 0.330 M HCl = .095 x .33 = .03135 moles

mole ratio of  hydrochloric acid to barium hydroxide

= .03135 /  .01864 = 1.68

theoretical ratio = 2 /1 = 2

As the theoretical ratio is more , therefore HCl is the limiting reactant  .

Answer:

3.87 mol N

General Formulas and Concepts:

Chemistry - Atomic Structure

Explanation:

Step 1: Define

54.2 g N

Step 2: Identify Conversions

Molar Mass of N - 14.01 g/mol

Step 3: Convert

[tex]54.2 \ g \ N(\frac{1 \ mol \ N}{14.01 \ g \ N} )[/tex] = 3.86867 mol N

Step 4: Check

We are given 3 sig figs. Follow sig fig rules and round.

3.86867 mol N ≈ 3.87 mol N

Answer:

This happened because of evaporation, the sun evaporated the water.

Answer:

Because if you place the plate filled with water in the sun then a small amount of water will be dried up by the sun's heat.

Answer:

wouldn't it be 52

Explanation:

Answer:

please mark as brainliest

Explanation:

ans: Gas

The particles of matter in the gaseous state are neither close together nor fixed in place. The gas expands to fill its container. Thus, a given number of particles will have the greatest volume in the gas state.30‏/06‏/2014

Answer: It is a

Explanation:

Answer:

eat well, stay well, and have fun ∛π⇅πΔΔΔ≅≅⇵↑↓∫∫↑

Explanation:

Answer:

Chemical element symbols are one- and two-letter abbreviations for the element names. They are used to make the periodic table and chemical formulas easier to read. You can combine the symbols to make words. Here is a list of English words made from periodic table element symbols. There are thousands of words that can be written using these symbols, so experiment to see if you can write your name or fun messages that show your chemistry savvy.

Answer:

2D refers to the term “two-dimensional.”

3D refers to the term “three-dimensional.”

Explanation:

Circle, triangle, square, rectangle, and pentagon are some of the most common examples of 2D shapes.

Cylinder, pyramid, cube, and prism are some of the most common examples of 3D shapes.

Answer:

Both the motion of the particles in the substance and the temperature of the substance increase.

Answer The motion of the particles in the substance increases, and the temperature of the substance decreases.  

Explanation:

Answer:

In explanation,

Explanation:

Tests of Big Bang: The CMB. The Big Bang theory predicts that the early universe was a very hot place and that as it expands, the gas within it cools. Thus the universe should be filled with radiation that is literally the remnant heat left over from the Big Bang, called the “cosmic microwave background", or CMB.

Answer:

3

Explanation:

The reaction is given as:

           H₂S   +   O₂   →  SO₂    +    H₂O

Let us balance the chemical equation.

 We take some letters and we use them as the coefficient to balance the equation;

          aH₂S   +   bO₂   →  cSO₂    +    dH₂O

Now,

  Conserving H;

         2a  = 2d

 Conserving S;

         a = c

 Conserving O;

        2b  = 2c + d  

Let a  = 1, d  = 1, c  = 1, b  = [tex]\frac{3}{2}[/tex]  and multiply through by 2;

    a = 2, b  = 3, c  = 2 and d = 2

So, the balanced reaction equation is given as;

    2H₂S   +   3O₂   →  2SO₂    +    2H₂O

Answer:

My guess is b or c but its robably wrong

Explanation:

I just also need points sorry <3

Answer:

This equation is a double reaction

Explanation:

I hope this is the answer

Answer:

ca(OH)2 is the base and CaCI2 is the salt

Explanation:

Answer:

1. It is a covalent bond and all covalent bonds have low melting points

Explanation:

Answer:

covalent bonds............

covalent bonds

Ionic bonds structure when a nonmetal and a steel alternate electrons, while covalent bonds form when electrons are shared between two nonmetals. An ionic bond is a type of chemical bond formed through an electrostatic enchantment between two oppositely charged ions.

Bunsen burner is an instrument which is used as a source of heat using natural gas or petrol. It is used for the heating, sterlization, and combustion. Bunsen burner is named after its inventor Robert bunsen.

Burner provide a single, continuous flame by mixing gas with air in a controlled fashion. The ratio of gas to air that is mixed together can be manually adjusted, allowing the user to control the intensity, temperature, and size of the flame.

Answer:

D

Explanation: