Atomic structure Questions and Answers

What did Ernst Rutherford discover through his gold foil experiment? The nucleus is small, dense, and positively charged. Atoms are dense and have a nucleus. Alpha particles are positively charged. Electrons are negatively charged particles.

22. Base your answer to this question on the passage below and on your knowledge of social studies. (It) brought the potato, the pineapple, the turkey, dahlias, sunflowers, magnolias, maize, chillies and chocolate across the Atlantic. On the other hand, tens of millions died in the pandemics of the 16th century, victims of smallpox, measles and the other diseases brought by Europeans (and don't forget that the African slave trade was begun by the Europeans, to replace the workforce they had decimated).". - Michael Wood, BBC History (adapted) Which historical development is being described in this quotation? 1. establishment of the line of Demarcation 2. creation of the Hanseatic League 3. Columbian exchange 4. Glorious Revolution

[References] The Freons are a class of compounds containing carbon, chlorine, and fluorine. While they have many valuable uses, they have been shown to be responsible for depletion of the ozone in the upper atmosphere. In 1991, two replacement compounds for Freons went into production: HFC-134a (CH₂FCF,) and HCFC-124 ( CHCIFCF3). Calculate the molar masses of these two compounds. (Round your answer to two decimal places.)

Which of the following pairs are used in Rutherford's experiment? Alpha particle and cathode ray Cathode ray and gold foil Gold foil and alpha particle Gold foil and electrons

Assuming that the ion formed has a noble gas configuration, write a chemical equation that shows the formation of a barium ion from a neutral barium atom. Represent electrons as e Left Side ⇒ Right Side

What is the correct set up and answer for NH4OH? (remember round to the tenths) 23.0 + 5(1.0) + 16.0 = 44.0 g 14.0+ 4(1.0) + 16.0 = 34.0 g 14.0+ 5(1.0) + 16.0 = 35.0 g 14.01 +5(1.01) + 15.99 = 35.05 g

What type of evidence does Orwell use in this passage? (a) fact (b) statistic (c) quotation (d) hypothetical

Matter has mass and takes up space. Atoms are basic building blocks of matter, and cannot be chemically subdivided by ordinary means. What's an atom made of? Even though an atom is really small, it is made of even smaller particles. It's basically made of 3 tiny subatomic particles: _______________ ________________ ________________ Parts of an Atom ____(a)_________: in the nucleus (positive) charge 1 amu _____(b)________: in the nucleus o (no) charge 1 amu ______(c)_______: in the electron cloud - (negative) charge o amu The center of an atom is called the_______(d)______ The nucleus contains 2 types of particles: ______(e)_______= positive (+) charge______(f)_______= no charge, neutral This means the nucleus is always positive. The Outside of the Atom: Surrounding the nucleus is a cloud of electrons. ______(g)_______spin quickly. Are negatively (-) charged are very small. Have a mass of O AMU.

How are the Bohr model and the quantum mechanical model of the hydrogen atom similar? How are they different?

Which of the following molecular formulas are also empirical formulas? If the formula empirical formula, write the empirical formula for that molecule. a. Al₆O₉ b. PbO₂ c. MgCO₃ d. C₈H₁₈O₂ e. Si₃H₉O₂

A bright violet line occurs at 435.8 nm in the emission spectrum of mercury vapor. What amount of energy, in joules, must be released by an electron in a mercury atom to produce a photon of this light?

Which set of quantum numbers is correct and consistent with n = 4? A) l = 3 ml = -3 ms = +½ B) l = 4 ml = +2 ms=-½ C) l = 2 ml = +3 ms =+½ D) l = 3 ml = -3 ms = +1

(A) What is the hybridization of the central atom in SeH₂? What are the approximate bond angles in this substance? (B) What is the hybridization of the central atom in SO₂? What are the approximate bond angles in this substance?

Select the examples in which the electron configurations correctly match the given atoms in their ground states. (select all that apply, wrong choices will be penalized) (A) Ar = 1s²2p⁶3d¹⁰ (B) S = [Ne] 3s²3p⁴ (C) Cr = [Ar] 4s¹3d⁵ (D) Cu = 1s²2s²2p⁶3s²3p⁶4s²3d⁹ (E) Cu = 1s²2s²2p⁶3s²3p⁶4s¹3d¹⁰

Based on formulas alone, which is the stronger acid? HCI HF Based on formulas alone, which is the stronger acid? H₂O H₂S

As the atoms in Period 4 of the Periodic Table are considered from left to right, the atoms generally show 1. an increase in radius and an increase in ionization energy 2. an increase in radius and a decrease in ionization energy 3. a decrease in radius and an increase in ionization energy 4. a decrease in radius and a decrease in ionization energy

The wavelength of one line in the emission spectrum of C is 458 nm. What is the energy of one photon with this wavelength? (Hint: h=6.626 x 10^-34 J s)

Which of the following statements best describes the basic structure of an atom? Electrons and protons are in motion around a nucleus that contains neutrons. ONeutrons are in motion around a nucleus that contains protons and electrons. Protons are in motion around a nucleus that contains electrons and neutrons. Electrons are in motion around a nucleus that contains protons and neutrons.

What happens to an electron when it moves from the ground state to an excited state? An electron loses energy as it drops to a lower energy level. An electron gains energy as it drops to a lower energy level. An electron loses energy as it jumps to a higher energy level. An electron gains energy as it jumps to a higher energy level.

Which is the best explanation for why the radius of a phosphorous atom is smaller than that of a magnesium atom? Phosphorous has a greater atomic mass. Phosphorous has more protons in the nucleus. Phosphorous has more neutrons in the nucleus. Phosphorous has a greater electronegativity value.

An ion from a given element has 56 protons and 54 electrons. What is the charge on the ion? What is the name of the element? What is the symbol for the ion?

Microwaves, such as those used for radar and to heat food in a microwave oven, have wavelengths greater than about 3 mm. What is the frequency of radiation of wavelength 9.64 mm? Answer in units of s-¹.

Which one of the following reactions would produce the largest amount of heat per mole of hydrogen? A) C (s) + 2 H₂ (g) → CH4 (g) ΔH° = -74.9 kJ/mol B) N₂O (g) + 3 H₂ (g) → N₂H4 (g) + H₂O (I) ΔH° = -316.8 kJ/mol C) 2 H₂ (g) + O₂ (g) → 2 H₂O (I) ΔH° = -571.6 kJ/mol D) N₂ (g) + 3 H₂ (g) → 2 NH3 (g) ΔH° = -91.8 kJ/mol

An ice cube is heated until it is completely vaporized. Which property in the ice cube changes during this process? The charge of the electrons in the atoms The speed of the water molecules The composition of the water molecules The atomic mass of the atoms in the ice

Consider the following: an administrative agency exercises powers that are akin to legislative powers (an administrative agency can issue rules and regulations); judicial powers (it can decide decides disputes within its area of expertise); and executive powers (it executes and enforces rules and regulations). In light of the confluence of powers in the same administrative agency, identify and discuss at least 2 constitutional objections to such a situation.

How many mL of 4.15M KCI is used to make 500. mL of 1.25M solution? a. 151mL b. 500mL c. 120 mL d. 10.3mL

Consider the element magnesium: a. Explain how you would determine the number of neutrons in a Calcium atom that has a mass number of 42. b. Another atom of Calcium has a mass number of 45. How does it compare to the above atom of Calcium?

An element has an atomic number of 6. How many protons and electrons are there in a neutral atom of this element? 3 protons and 3 electrons 6 protons and O electrons 6 protons and 6 electrons 12 protons and 6 electrons

What correctly describes the relationship between the spectrum of one atom and the spectrum of another? A. The number of visible spectral lines are identical for atoms; however, they have unique wavelengths. B. The visible lines are identical for all atoms; however, their intensities vary due to the electronic structure of the atom. C. The spectra are similar, however, the lines are offset by a certain wavelength either to higher or lower wavelengths due to the number of protons in the nucleus of the atoms D. The visible spectral lines for an element are unique and show no relationship to the spectra for atoms of other elements.

Use the dropdowns to create a correct and complete isotope notation. An isotope has 108 neutrons and 72 protons. The correct isotope is:

Sort the following from greatest energy (1.) to smallest energy (6.) of a photon. Radio Waves Microwave Radiation X-Rays Ultraviolet Radiation Visible Light Infrared Radiation

What is a possible set of quantum numbers for one of silver's electrons in the 4d energy sublevel? Note: Since an electron only has a single set of quantum numbers, please enter only a single number in each of the blanks. n = l = ml =

At 25.0 °C the Henry's Law constant for nitrogen trifluoride (NF) gas in water is 7.9 × 10^-4 M/atm. Calculate the mass in grams of NF3, gas that can be dissolved in 1350. mL of water at 25.0 °C and a NF3, partial pressure of 2.72 atm. Round your answer to 2 significant digits.

Enter an abbreviated electron configuration for sodium: Express your answer in complete form, in order of increasing energy. For example, [He]2s^2 2p^2 would be entered as [He]2s^2 2p^2. Enter an abbreviated electron configuration for beryllium: Express your answer in complete form, in order of increasing energy. For example, [He]2s^2 2p^2 would be entered as [He]2s^2 2p^2.

Which of the following is a postulate of the atomic theory? Some matter is discontinuous. When a chemical reaction takes place, the atoms change into new atoms. The atoms of an element are alike, and different from the atoms of every other element. Some matter is continuous.

Use the periodic table to give the symbol of the element that meets the following conditions. You may want to reference (Page) Section 5.5 while completing this problem. The element has two electrons in the 5p sublevel. Express your answer as a chemical symbol.

tellurium Express your answer in condensed form, in order of increasing orbital energy. For example, [He]2s^2 2p^2 would be entered as [He]2s^2 2p^2 rubidium Express your answer in condensed form, in order of increasing orbital energy. For example, [He]2s^2 2p^2 would be entered as [He]2s^2 2p^2

Which of the following orbitals are possible in an atom: 1s, 1p, 1d, and 5f? Check all that apply. 5f 1s 1d 1p

How many 3d electrons are in Ni? Express your answer as an integer. How many 4p electrons are in Y? Express your answer as an integer.

A certain shade of blue has a frequency of 7.15 x 10^14 Hz. What is the energy of exactly one photon of this light? Planck's constant is h = 6.626 x 10^-34 J.S.

An element has 24 protons in its nucleus. (a) Identify this element. (b) Write the symbol for the element's isotope. That will have a mass closest to its average atomic mass. (c) How many neutrons are in the isotope you described in part (b)? (d) How many electrons are in neutral atoms of this element? (e) How many times heavier than ¹2C is the average atom im of this element?

What does the mass number of an atom tell us? the number of electrons in the atom the number of protons in the atom the number of neutrons in the atom the total number of protons and neutrons in the atom

Give the nuclear symbol for the isotope of gallium, Ga, that contains 40 neutrons per atom. Replace the question marks with the proper integers.

Write an equation that shows the formation of a cesium ion from a neutral cesium atom. Represent electrons as e. If a box is not needed, leave it blank. If the coefficient is 1, do not write it.

Give the nuclear symbol (isotope symbol) for the isotope of bromine, Br, that contains 46 neutrons per atom. Replace the question marks with the proper integers.

Find the missing component of an effective conclusion: In conclusion, speed limits are in place for a reason. With the overall safety of the public in mind, speed limits should always be followed and enforced. Is getting to your destination a few minutes earlier worth risking the lives of everyone or everything you pass along the way? Restate your thesis statement in a different way, maintaining the same overall meaning. Restate your main points in a way that shows how they are related and why they matter. State the conclusion of your topic in clear, concise language.

For the following isotope symbol, 93 41 X, indicate the following: Number of protons Report your answer as a whole number. Number of neutrons Report your answer as a whole number. Element symbol Report your answer as a chemical symbol.

Select the appropriate dropdown options to correctly complete each of the following statements. Electrons and other submicroscopic particles exhibit behavior. When the position of a particle is measured more accurately, the measured momentum of the particle is -- In the quantum mechanical model of the atom, the wavefunctions (y) represent The location of electrons in atoms is most accurately described in terms of electron - i.e. the of an electron being within a given location with respect to the nucleus.

Enter the full ground state electron configuration for each element given below. For superscripts, use the symbol before the number. For example, 2s² should be entered as: 2s^2. In between sublevels add a space. For example, 3s²3p3 should be entered as: 3s^2 3p^3. Be sure to list the subshells in order of increasing energy.

Which activity best demonstrates Ernest Rutherford's creativity? questioning the correctness of the plum pudding model designing an experiment to test the plum pudding model making observations about the gold foil experiment summarizing the conclusions from the gold foil experiment as a theory