The Atomic Theory RHS

Dalton incorporated the law of conservation of mass into his atomic theory by asserting that

• atoms are indivisible

• atoms of different elements have different properties

• matter is composed of atoms

• atoms can be destroyed in chemical reactions

Tags

NGSS.HS-PS1-7

In oxides of nitrogen, such as N₂O, NO, NO₂, and N₂O₃, atoms combine in small whole-number ratios. This evidence supports the law of

• conservation of mass

• multiple proportions

• definite composition

• mass action

If two or more compounds are composed of the same two elements, the ratio of the masses of one element that combine with a fixed mass of the other element is a simple whole number. This is a statement of the law of

• conservation of mass

• multiple proportions

• definite proportions

• mass action

According to the law of conservation of mass, when sodium, hydrogen, and oxygen react to form a compound, the mass of the compound is __ the masses of the individual elements.

• equal to

• greater than

• less than

• either greater than or less than

Tags

NGSS.HS-PS1-7

The principles of the atomic theory recognized today were conceived by

• Avogadro

• Bohr

• Dalton

• Rutherford

Which concept in Dalton's atomic theory has been modified?

• all matter is composed of atoms

• atoms of different elements have different properties and masses

• atoms can combine in chemical reactions

• atoms cannot be divided

The atomic theory proposed by Dalton has been

• totally discarded

• expanded and modified

• accepted unchanged to the present day

• found to be plagiarized

In a glass tube attached to a voltage source, electrical current passes from the negative electrode, called the __, to the other electrode.

• cathode

• anode

• electron

• millikan

When an electrical current is passed through a glass tube, it caused the surface of the tube directly across from the cathode to glow. Scientists concluded that

• a magnetic field was produced

• the particles of the beam were negatively charged

• there was gas in the tube

• atoms were indivisible

Experiments with cathode rays led to the discovery of the

• proton

• nucleus

• neutron

• electron