Ruben's Series
Elements, Compounds and Mixtures
protons and electrons as well as the arrangement of the electrons in the radius shells.
Draw the electronic configuration of the atom showing clearly the position of the
State the number of electrons that will make the following shells full
M-shell i.K-shell i L-shell
7 What is the name given to the path through which electrons move round the nucleus.
Anatom Y has the Atomic number 13. It loses three electrons in order to become stable.
What is the Proton number and the Electron number of the atom?
before itloses the electrons.
after losing electrons.
illustration
pt Name the type of ion formed by the atom when it lost three electrons. Show by
10 State two differences between atom and ion.
9. What is an ion?.State the difference between cations and anions.
1. Magnesium has an Atomic number of 12.
Draw a diagram to show the distribution of electrons in the atom
State the electronic configuration of the atom,
h. How many electrons does the M-shell take?
2. An atom has Atomic number of ll and a Mass number of 23.
Determine the number of protons, electrons and neutrons of the atom X.
Draw the electronic shell of the atom X.
What is the electronic configuration of the atom X?
13. What is valency? State the valency of the following elements.
Calcium Oxygen, Carbon ,Sodium and Chlorine.
14. What is a radical?Give four examples of radicals.​

Explanation:

Four elements, hydrogen, carbon, oxygen and nitrogen, are the major components of most organic compounds. Consequently, our understanding of organic chemistry must have, as a foundation, an appreciation of the electronic structure and properties of these elements. The truncated periodic table shown above provides the orbital electronic structure for the first eighteen elements (hydrogen through argon). According to the Aufbau principle, the electrons of an atom occupy quantum levels or orbitals starting from the lowest energy level, and proceeding to the highest, with each orbital holding a maximum of two paired electrons (opposite spins).



Electron shell #1 has the lowest energy and its s-orbital is the first to be filled. Shell #2 has four higher energy orbitals, the 2s-orbital being lower in energy than the three 2p-orbitals. (x, y & z). As we progress from lithium (atomic number=3) to neon (atomic number=10) across the second row or period of the table, all these atoms start with a filled 1s-orbital, and the 2s-orbital is occupied with an electron pair before the 2p-orbitals are filled. In the third period of the table, the atoms all have a neon-like core of 10 electrons, and shell #3 is occupied progressively with eight electrons, starting with the 3s-orbital. The highest occupied electron shell is called the valence shell, and the electrons occupying this shell are called valence electrons.

The chemical properties of the elements reflect their electron configurations. For example, helium, neon and argon are exceptionally stable and unreactive monoatomic gases. Helium is unique since its valence shell consists of a single s-orbital. The other members of group 8 have a characteristic valence shell electron octet (ns2 + npx2 + npy2 + npz2). This group of inert (or noble) gases also includes krypton (Kr: 4s2, 4p6), xenon (Xe: 5s2, 5p6) and radon (Rn: 6s2, 6p6). In the periodic table above these elements are colored beige.

The halogens (F, Cl, Br etc.) are one electron short of a valence shell octet, and are among the most reactive of the elements (they are colored red in this periodic table). In their chemical reactions halogen atoms achieve a valence shell octet by capturing or borrowing the eighth electron from another atom or molecule. The alkali metals Li, Na, K etc. (colored violet above) are also exceptionally reactive, but for the opposite reason. These atoms have only one electron in the valence shell, and on losing this electron arrive at the lower shell valence octet. As a consequence of this electron loss, these elements are commonly encountered as cations (positively charged atoms).

The elements in groups 2 through 7 all exhibit characteristic reactivities and bonding patterns that can in large part be rationalized by their electron configurations. It should be noted that hydrogen is unique. Its location in the periodic table should not suggest a kinship to the chemistry of the alkali metals, and its role in the structure and properties of organic compounds is unlike that of any other element.

How many moles are in 212.46 grams of H2SO4?

TRUE or FALSE?
Science​

The process that is the opposite of sublimation is called deposition. Use the example of frost formation to infer why this process has this name.

A gas has a of 590 mi. At a temperature What volume will the gas occupy at 30.0öc.1 Which gas law is this

Which of the following statements is true about a light-year?

A) It is the distance to Alpha Centauri.
B) It is shorter than the astronomical unit.
C) It is used to measure long periods of time.
D) It is used to measure long distances in space.

What causes a repeating pattern of day and night

What is the concentration of a solution with a volume of 2.50 liters containing 630. grams of calcium phosphate, Ca3(PO4)2?

What is the definition of a Double Displacement Reaction?

When does the object change direction?
Distance vs. Time
50
40
30
20
10
c
D
2
6
8
10
Time
F

5. Which set of coefficients will balance this chemical
equation?
_C2H4(g) +
O2(g) → 2CO2(g) + 2H2O(g)
A. 1.2
B. 1.3
C. 2.3
D. 2.5

About what percent of the Earth is covered in salt water oceans?
A.84%
B.71%
C.49%
D.65%

(b) Which solution has a higher percent ionization of the acid, a 0.10M solution of HC2H3O2(aq) or a 0.010M solution of HC2H3O2(aq) ? Justify your answer including the calculation of percent ionization for each solution.

What should be the first thing human try and research/solve with genetics?

Which of the following (H+) values describes a neutral solution?
O 10-1M
O 10-7M
10-14 M
O 10-12M

Dihydrogen sulfide reacts with oxygen gas to form sulfur dioxide and water. How many moles of oxygen gas will react when 0.6469 moles of water are formed?

intrusive igneous rock forms when the cooling of magma takes place fast on the top of the Earth's surface. A. True B. False

why do men
thats it that’s the question

Would you see more living things in a Biome or an Ecosystem?

Use the information and table to answer the following question.
Scientists use either a melting år freezing point apparatus to determine the melting points of the following unknown compounds as part of
their investigation. Based on the melting points, the scientists determine the bond type and record the results in the table as shown.
Unknown Compound
Compound 1
Exhibits
Compound 2
Compound 3
Compound 4
Melting Point
772°C
17°C
960°C
-56°C
Which statement correctly identifies the ionic compounds and why?
A Compounds 1 and 3 are lonic. Because covalent compounds are composed of oppositely charged ions that are attracted to one
another, they require more energy to melt than ionic bonds.
O B. Compounds 2 and 4 are ionic. Because covalent compounds are composed of oppositely charged ions that are attracted to one
another, they require more energy to melt than ionic bonds.
C. Compounds 2 and 4 are ionic. Because ionic compounds are composed of oppositely charged ions that are attracted to one another,
they require more energy to melt than covalent bonds,
D. Compounds 1 and 3 are ionic. Because ionic compounds are composed of oppositely charged ions that are attracted to one another,
they require more energy to melt than covalent bonds.

Consider the following representation of a reaction mechanism.

Step 1: A+A → C+E (slow)
Step 2: E + B → A+D (fast)
Overall reaction: A + B → C + D

What should appear in the rate law for the reaction above?

A) only A and B because they are reactants in the overall reaction

B) only C and C because they are products in the overall reaction

C) only A because it is the reactant in the rate-determining step

D) only E and B because they are the reactants in the rate-determining step​

The boiling point of a liquid is the temperature at which its ____________ _____________ is equal to ____________ ____________.(atmospheric pressure, vapor pressure

what element is solid at room temperature shiny malleable and a good conductor of heat

What is electroluminescence? Give one example.​

A cube, with a mass of 21 g is dropped in a graduated cylinder with 10 mL
water. The water level rises to 24 mL when the cube is added. What is the
cube's density (don't forget units)

What volume of hydrogen is necessary to react with 6.25g of nitrogen to produce ammonia?
(Assume constant temperature and pressure.)
A. 30L
B. 15L
C. 6.2L
D. 12.5L

Photosynthesis is a process that can be performed by many autotrophic organisms within the ecosystem. Without photosynthetic organisms, the food chain would not be able to sustain the energetic needs of the ecosystem. Whic statement compares the energy transformations that occur in the ecosystem within photosynthetic organisms?

A Solar energy is converted to thermal energy, which increases food availability for the ecosystem.

B Solar energy is converted into chemical potential energy, which is found in the products like glucose.

C Chemical erlergy in carbon dioxide is converted into solar energy, which provides a mechanism to produce food for the ecosystem.

D Kinetic energy of the reactants is converted to potentia. energy in the products, which can be metabolized within the ecosystem.​

_8. Which factor(s) will increase the solubility of a solid?
C. increase surface area
D. increase agitation.
A. Increase temperature B.increase pressure

Group 2, Period 6
whats the answer for this please it's on the periodic table

Which of the following is the most important reason for people to carefully manage natural resources?
A.) Recycling facilities are being constructed around the world.
B.) Underground reserves of oil have not yet been discovered.
C.)Technology that uses natural resources more efficiently are being developed.
D.)The growing human population is putting increasing demands on natural resources.

5. What mass of the following solutes will dissolve in 100 ml of water?

KNO3 at 50o C? ______________________________

NH4Cl at 50o C? _________________________________

NaNO3 at 50o C? _______________________________