Physical science Unit three test review

A current through a 10 ohm resistor connected to a 120 V power supply is

12 Amps

When 1 pair of ohm resistors are connected in series, their combined resistance is

2 ohms, and when in parallel, 1/2 ohm

Which set of coefficients balance the following chemical equation ___AlO3H3-> ___Al2O3 + ___H2O

2,1,3

The current through two identical lightbulbs connected in a series is 0.25 A. The voltage across both bulbs is 110 V. The resistance of the single light bulb is

220 ohms

The electric power of a lamp that carries 2 A at 120 V is

240 watts

The nucleus of an electrically neutral iron atom contains 26 protons. How many electrons does iron atom have

26

Two charges separated by 1 m exert a 1N force on each other. If the magnitude of each charge is double, the force on each charge is

4 N

Which side of coefficient balance the following chemical equation ___PH3+ ___O2-> ___P4O10+___H2O

4,8,1,6

How many shows are occupied by electrons in the gold atom

6

An element found in another galaxy exists as two isotopes. If 80% of the items have an atomic mass of 80 amu and the other 20% have an atomic mass of 82 amu, what is the approximate atomic mass of the element

80.4 amu 80 x .8 + 82 x .2 64+ 16.4 =80.4

An element that tends to gain electrons during chemical reaction is probably

A nonmetal

When an electron in an atom is excited from a lower energy level to higher one

A photon is absorbed

Ammonia, NH3, is more polar than is borane, BH3, because it

All of the above It's hydrogens are not exactly opposite one another, has a lone pair of electrons, and is less symmetrical than borane

A molecule has

All of these Structure, mass, energy

Neutral hydrogen atom can attract an additional electron

Because the additional electron finds room in the valence shell

Two lamps, one with thick filament in one within tournament or connected in parallel to a battery. The voltages greatest across the lamp with the

Both voltages are the same

Which of the following shows elements in order of increasing atomic size (CL atomic number 17; K atomic number 19; Br atomic number 35; Rb atomic number 37)

Cl, Br, K, Rb

The chemical properties of matter mostly come from it's

Electrons

The number of elements in period is

Equal to the electron capacity of the shells

An electron D excites from the fourth quantum level to the third and then directly to the first. Two frequencies of light are admitted. How do their combine energies compare to the energy of the single-frequency that would be admitted by The excitation from the fourth level directly to the first level? Answer: they combine energies of the two frequencies emitted by one electron is

Equal to the energy of the single frequency

How many electrons in the outermost shell of phosphorus (P, atomic # 15)

Five

Which of the following is an example of chemical change

Gasoline being used in the engine of a car producing exhaust

Which of the following would cause the current through an electrical circuit to decrease

Increase the resistance

An electron in a 7S orbital has more energy than one in a 1s orbital because

It is farther from the nucleus

As atoms get more massive they become smaller in size because

More mass means more protons, which act electrons and closer to the nucleus

During a chemical reaction

Old atoms stick around merely switching partners

An electron is pushed into an electric field word acquires a one volt electrical potential. If two electrons are pushed the same distance into the same electric field, the electric potential of the two electrons is

One volt

In an electrically neutral atom, the number of protons in the nucleus is balance by an equal number of

Orbital electrons

One element is distinguish from another by the number of

Protons

The weight of matter comes mostly from

Protons

What element is distinguish from another by the number of

Protons

When the distance between two charges is halved, the electrostatic Force between the charges

Quadruples

How many shells are occupied by electrons in the gold atom (Au, atomic # 79)

Six

Supposed certain Adam possess is only four distinct energy levels. Assuming that all transitions between levels are possible, how many spectral lines will decide an exhibit

Six

Is 60 W lightbulb and a 100 W lightbulb are connected to a 120 V outlet. Which light has more current in it

The 100 W bulb

A 60 W lightbulb in a 100 W lightbulb are each rated at 120 V. Which lightbulb has a larger resistance

The 60 Watts bulb

Why are the atomic masses in the periodic table not whole numbers

The atomic masses are average atomic masses

How is a physical change different from a chemical change

The chemical identity of a substance is not altered during a physical change

The greater the difference in electronegativity between two covalently bonded atoms

The greater the polarity

Compared to the electric current that flows in the filming of a lamp, the amount of current that flows in the connecting wire is

The same

How many electrons are unpaired in the outer most shell of aluminum (Al, atomic # 13)

Three

Which of these items has the greatest amount of electrical charge in its nucleus

Uranium

Two wires, A and B, with circular cross-section have identical links and are made of the same material. Yet, wire A has four times the resistance of wire B. Which wire, a or B, has the largest diameter

Wire b

Which force binds atoms together to form molecules

electrical

A hydrogen atom does not form more than one covalent bond because it

has only one electron to share

What drives an atom to form a covalent bond: its nuclear charge or the need to have a filled outer shell

its nuclear charge

Which of the following are electrically neutral

neutron

What type of chemical bond would you expect between two chlorine atoms (Cl atomic number 17)

nonpolar covalent

To say a chemical equation is balanced means the

number of times each element appears as a reactant is equal to the number of times it appears as a product

The purpose of coefficients in chemical equations is to make

the number of times each element appears as a reactant and as a product the same.

A circuit is powered with a battery. Current flows

through both the battery and the rest of the circuit.