Based on the diagram shown, how many electrons does this atom have?
a.six
b.three
c.nine
d.one

Answer:

D

Explanation:

A The calcium chloride dissolves in solution

B The mass of the solution totals 20 g

C The temperature of the solution is 35 degrees

D The solution became lighter in color

The correct answer would be that the solution became lighter in color.

An increase in temperature can also be considered a sign of a chemical reaction but in this case, the dissolution of calcium chloride in water is in itself exothermic.

A change in the mass of the final solution could also be considered a sign of a chemical reaction but in this case, the total mass equals the addition of the individual masses of the reactant.

The dissolution of calcium chloride in water is not enough as evidence of a chemical reaction. Dissolution can be a physical change of which, the evaporation of the water would retrieve the solute.

A change in color, however, is one of the evidence to establish that a chemical reaction has occurred.

The correct option is D.

Answer:

3. Shared and unshared electron pairs repel each other as much as

possible

Explanation:

The variations in the bond angles of molecules and ions can be explained using the valence shell electron pair repulsion theory.

The VESPR model determines the total number of electron pairs (TEP) surrounding the central atom of a specie. The TEP consists of bond pairs BP and lone pairs LP.

All the electron pairs will orient themselves in such a way as to minimize the electrostatic repulsion between them.

The repulsion determines the geometry of the covalent bonds around the central atom. As the number of lone pairs increases from 0 to 2, the bond angles diminishes progressively.

Answer:

24.66%

Explanation:

To find the percent of water (H2O) in the following compound: Zn3(PO4)2. 7H2O

The atomic mass of the elements are as follows:

Zn = 65g/mol

P = 31g/mol

O = 16g/mol

H = 1g/mol

Hence, molar mass of the compound is as follows:

65(3) + {31 + 16(4)} 2 + 7{1(2) + 16}

195 + 95(2) + 7(18)

195 + 190 + 126

511g/mol

Molar mass of 7H2O

= 7(18)

= 126g/mol

Hence, the percent of H2O in the compound is:

Molar Mass of 7H2O/molar mass of compound × 100

= 126/511 × 100

= 0.2466 × 100

= 24.66%

Energy required to vaporize : 32.3 kJ

The heat to change the phase can be formulated :

Q = mLf (melting/freezing)

Q = mLv (vaporization/condensation)

Lf=latent heat of fusion

Lv=latent heat of vaporization

Mass of water = 14.27 g

Latent heat of vaporization ( boiling point of 100 ºC) :  2260 J/g

Energy required :

[tex]\tt Q=m.Lv\\\\Q=14.27\times 2260\\\\Q=32250.2~J\approx 32.3~kJ[/tex]

Answer:

a

Explanation:

Because that is the answer

Answer:

the advantage of using Microsoft Excel to create a graph, as opposed to pen and paper is it will help you get the right answer

Explanation:

Answer:

A: Endoplasmic reticulum

B: Chroloplast

C: Mitochondrion

D: Cytoplasm

E: Cell wall

Explanation:

Answer:

the answer is c IBr3

Explanation:

The chemical formula for iodine tribromide is IBr₃ as it has 1 iodine and 3 bromine atoms.

Chemical  formula is a way of representing the number of atoms present in a compound or molecule.It is written with the help of symbols  of elements. It also makes use of brackets and subscripts.

Subscripts are used to denote number of atoms of each element and brackets indicate presence of group of atoms. Chemical formula does not contain words. Chemical formula in the simplest form  is called empirical formula.

It is not the same as structural formula and does not have any information regarding structure.It does not provide any information regarding structure of molecule as obtained in structural formula.

There are four types of chemical formula:

1)empirical formula

2) structural formula

3)condensed formula

4)molecular formula

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Answer:

These are all in order....

Explanation:

- closed system usually absorbs thermal energy from its surroundings, which is heat transfer into the system

- a solute is a substance dissolved in another substance, known as a solvent

- A solvent is a substance that dissolves a solute, resulting in a solution. A solvent is usually a liquid but can also be a solid, a gas, or a supercritical fluid

- a liquid mixture in which the minor component (the solute) is uniformly distributed within the major component (the solvent)

- a nuclear reaction in which a heavy nucleus splits spontaneously or on impact with another particle, with the release of energy

- a nuclear reaction in which atomic nuclei of low atomic number fuse to form a heavier nucleus with the release of energy.

- Half-life is the time required for a quantity to reduce to half of its initial value

- the determination of the age or date of organic matter from the relative proportions of the carbon isotopes carbon-12 and carbon-14 that it contains. The ratio between them changes as radioactive carbon-14 decays and is not replaced by exchange with the atmosphere.

- any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as the system's mass cannot change, so quantity can neither be added nor be removed

Given :

Volume of stock solution, [tex]V_s = 20\ mL[/tex].

Volume of diluted solution, [tex]V_d = 400 \ mL[/tex].

Molarity of diluted solution, [tex]M_d = 1.44\ M[/tex].

To Find :

The concentration of the stock solution.

Solution :

We know, dilution factor is given by :

[tex]D.F=\dfrac{V_ {diluted}}{V_{stock}}[/tex]      ....1)

and [tex]D.F= \dfrac{M_{stock}}{M_{diluted}}[/tex]     ....2)

Putting volume in above equation, we get :

D.F = 400/20

D.F = 20

Putting value of D.F in equation 2) we get :

[tex]\dfrac{M_{stock}}{M_{diluted}} = 20\\\\M_{stock} = 20\times 1.44\\\\M_{stock} =28.8\ M[/tex]

The concentration of stock solution is nearest to 30 M.

Therefore, the correct option is 1) 30 M.

Answer:

A

Explanation:

The molecule with the strongest intramolecular bond is HF. Hydrogen fluoride is the answer due to the strong and highly electronegative nature of Fluorine.

The molecule with the strongest internal bond is HF and the correct option is option A.

An intramolecular bond, also known as a chemical bond, refers to the attractive forces that hold atoms together within a molecule. It involves the sharing, transferring, or rearrangement of electrons between atoms to achieve a more stable configuration.

There are three primary types of intramolecular bonds:

Thus, the ideal selection is option A.

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Answer:

by moving between defined energy levels

Answer:

Electric Patterns and has many different variations.

Explanation:

Google

Answer:

velocity ratio is defined as the ratio of distance moved by effort and load in the same time interval

Explanation:

Answer:

The correct answer for this question would be B) Protons

Explanation:

I got it right on my test (Can I have brainlyest)

Answer:

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

[tex]n = \frac{N}{L} \\[/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

[tex]n = \frac{2.91 \times {10}^{22} }{6.02 \times {10}^{23} } \\ = 0.048338...[/tex]

We have the final answer as

Hope this helps you

Answer:

B

IS THE CORRECT ANSWER

Answer:

probably c

Explanation:

Answer: I feel like the correct answer is choice C but I really don’t know how to explain it..

The equation can be balanced using suitable integers multiplied either side and can be written as follows:

[tex]\rm Ca_{3} (PO_{4})_{2} + 4 H_{3}PO_{4} \rightarrow 3 Ca (H_{2}PO_{4})_{2}[/tex]

Thus the coefficient of H₃PO₄ is 4.

A balanced chemical equation of a reaction represents all the reactants and products in the perfect stoichiometric ratios where, the number of each element have to be equal in both sides.

The given reaction is an example of combination reaction. The equation can be balanced by equating the number of calcium in the product side by multiplying with 3 and then making the phosphate group also balanced by multiplying by 4 with  H₃PO₄.

Thus, the balanced chemical equation written above contains 3 calcium on both side and equal number of phosphate group (6) as well as hydrogens on both side where, the coefficient of  H₃PO₄ is 4

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Answer:

Agree

Explanation:

The rotation of earth happens about once every 24 hours.

Answer:

B. X

Explanation:

Answer:

The answer is D

Explanation:

Wave W is being diffracted, Wave X is being reflected, and waves Y and Z are being refracted.

Answer:

Decreases, increases

Explanation:

Depending on the number of electrons shared, covalent bonds may be single, double or triple. In  a single bond, two electrons are shared between bonding atoms. In a double bond, four electrons are shared between bonding atoms while in a tripe bond, six electrons are shared between bonding atoms.

The number of bonds is otherwise referred to as the bond order. The higher the bond order the higher the bond energy and the shorter the bond length. The bond length shortens due to an increase in the s character of the bond.

Answer:

If observed through the year, the constellations shift gradually to the west. This is caused by Earth's orbit around our Sun. In the summer, viewers are looking in a different direction in space at night than they are during the winter.

Explanation:

Answer:

there it the fact that the earthisspinningand so the starsare staying still and we are spinning

Answer:

Carbon dioxide goes in and oxogen comes out

P.S. Sunlight needed for this process to work

Explanation: