1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
dybincka [34]
3 years ago
15

Which of these is an isoelectronic series? 1) na+, k+, rb+, cs+ 2) k+, ca2+, or, s2– 3) na+, mg2+, s2–, cl– 4) li, be, b, c 5) n

one of these (a-d) save?
Chemistry
1 answer:
ss7ja [257]3 years ago
7 0
An isoelectronic series is where all of the ions listed have the same number of electrons in their atoms. When an atom has net charge of zero or neutral, it has equal number of protons and electrons. Hence, it means that the atomic number = no. of protons = no. of electrons. If these atoms become ions, they gain a net charge of + or -. Positive ions are cations. This means that they readily GIVE UP electrons, whereas negative ions (anions) readily ACCEPT electrons. So, to know which of these are isoelectronic, let's establish first the number of electron in a neutral atom from the periodic table:

Na=11; K=19; Rb=37; Cs = 55; Ca=20; S=16; Mg=12; Li=3; Be=4; B=5; C=6

A. Na⁺: 11-1 = 10 electrons
     K⁺: 19 - 1 = 18 electrons
     Rb⁺: 37-1 = 36 electrons

B. K⁺: 19 - 1 = 18 electrons
    Ca²⁺: 20 - 2 = 18 electrons
    S²⁻:  16 +2 = 18 electrons

C. Na⁺: 11-1 = 10 electrons
    Mg²⁺: 12 - 2 = 10 electrons
     S²⁻:  16 +2 = 18 electrons

D. Li=3 electrons
    Be=4 electrons
    B=5 electrons
    C=6 electrons

The answer is letter B.
You might be interested in
Which element in period 4 has the highest electronegativity
vova2212 [387]

<span>Electronegativity is the property of an element that measures the ability of it to attract and form electron bonds. The trend in the periodic table in terms of electronegativity decreases from right to left and from top to bottom. In the case of period 4, the element with the highest electronegativity is bromine. </span>

8 0
3 years ago
Read 2 more answers
What would happen if carbon -14 gained 1 proton and lost 1 neutron?
sleet_krkn [62]
D. To answer this question refer to the periodic table and think logically about it. Adding one proton increases the atomic number so you go along the row to Nitrogen. If you lose one neutron then the atomic mass decreases by 1 so 14-1 is 13.
4 0
3 years ago
Calculate the pH and pOH of 500.0 mL of a phosphate solution that is 0.285 M HPO42– and 0.285 M PO43–. (Ka for HPO42- = 4.2x10-1
jekas [21]

Answer: when concentrations of acid and base are same, pH = pKa

PH = 12.38 pOH = 1.62

Explanation: pKa= -log(Ka)= 12.38. PH + pOH = 14.00

8 0
3 years ago
Would you expect the wavelength of maximum absorbance for [Cu(NH3)4]2+ to be greater than or less than the wavelength of maximum
DENIUS [597]

Answer:

Less

Explanation:

Since [Cu(NH3)4]2+ and [Cu(H2O)6]2+ are Octahedral Complexes the transitions between d-levels explain the majority of the absorbances seen in those chemical compounds. The difference in energy between d-levels is known as ΔOh (ligand-field splitting parameter) and it depends on several factors:

  • The nature of the ligand: A spectrochemical series is a list of ligands ordered on ligand strength. With a higher strength the ΔOh will be higher and thus it requires a higher energy light to make the transition.
  • The oxidation state of the metal: Higher oxidation states will strength the ΔOh because of the higher electrostatic attraction between the metal and the ligand

A partial spectrochemical series listing of ligands from small Δ to large Δ:

I− < Br− < S2− < Cl− < N3− < F−< NCO− < OH− < C2O42− < H2O < CH3CN < NH3 < NO2− < PPh3 < CN− < CO

Then NH3 makes the ΔOh higher and it requires a higher energy light to make the transition, which means a shorter wavelength.

7 0
3 years ago
Given the chemical equation: 2 Pb + O2 → 2 PbO, if 51.8 grams of Pb are formed in this reaction, then 8.00 grams of O2 must have
Nutka1998 [239]

Answer:

If 51.8 of Pb is reacting, it will require 4.00 g of O2

If 51.8 g of PbO is formed, it will require 3.47 g of O2.

Explanation:

Equation of the reaction:

2 Pb + O2 → 2 PbO

From the equation of reaction, 2 moles of lead metal, Pb, reacts with 1 mole of oxygen gas, O2, to produce 2 moles of lead (ii) oxide, PbO

Molar mass of Pb = 207 g

Molar mass of O2 = 32 g

Molar mass of PbO = 207 + 32 = 239 g

Therefore 2 × 207 g of Pb reacts with 32 g of O2 to produce 2 × 239 g of PbO

= 414 g of Pb reacts with 32 g of O2 to produce 478 g of PbO

Therefore, formation of 51.8 g of PbO will require (32/478) × 51.8 of O2 = 3.47 g of O2.

If 51.8 of Pb is reacting, it will require (32/414) × 51.8 g of O2 = 4.00 g of O2

7 0
3 years ago
Other questions:
  • 1. Is this equation balanced? Explain your answer. Na + Cl2 → NaCl ?
    10·2 answers
  • Which law states that the volume of a gas is proportional to the miles of the gas when pressure and temperature are kept constan
    6·1 answer
  • Which action is the best example of a direct observation
    10·2 answers
  • ILL GIVE BRAINLIST!!!!!!
    11·2 answers
  • What happens to the charge if a nonmetal<br> takes two valence electrons?
    6·2 answers
  • What is the structure of epithelial cells?
    10·1 answer
  • 80g of Sodium react with 40g of Chloride to produce a product of Sodium Chloride. How many grams of sodium chloride will be pres
    11·1 answer
  • Which characteristic do electronegativity differences indicate about reactions between atoms
    12·1 answer
  • What is a control group?
    11·2 answers
  • An increase in blood CO2 or a decrease in blood ph will lead to which change in respiration?
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!