Chapter 2, Part I - Chemistry, The Central Science

According to Dalton's 4th postulate, in a given compound, the relative numbers and kinds of atoms are not constant.

Dalton's law, Postulate 3: The total mass of materials present after a chemical reaction is the same as the total mass present before the reaction.

Dalton's law of multiple proportions states that if two elements form more than one compound in a mixture (such as water H₂0 and hydrogen peroxide H₂O₂), then the ratio of the mass of the second element (such as the O₂ from the previous example) which combine with a fixed mass of the first element will always be ratios of small whole numbers. What this means is that in forming water, 8.0 g of oxygen combines with 1.0 g of hydrogen. In forming hydrogen peroxide, 16.0 g of oxygen combines with 1.0 g of hydrogen. Therefore, the number of hydrogens is the same making that fact irrelevant and thus the ratio of oxygen is all that is important 8.0 g O₂/16.0 g O₂, otherwise written as a 2:1 proportion. Which, according to the law of multiple proportions, is a whole number ratio. That said, complete the similar example using Carbon dioxide (CO₂) and Carbon monoxide (CO). In carbon monoxide, there is 1 gram of carbon for every _______ gram of oxygen. In carbon dioxide, there is 1 gram of carbon for every _______ gram of oxygen. Therefore, following the law of multiple proportions, what is the whole number ratio of oxygen that is produced (Hint: Cardon:Oxygen). 

Are elements and atoms the same thing?

It was not until the late 18th century that this person first postulated that elements that had been observed up until that point were comprised of smaller molecules called atoms. Who was this person?

_____________ is a mineral composed of pure carbon. It is the hardest naturally occurring substance known. It is also the only gem made of a single element. It has a luster to it that makes it a desirable jewelry piece. _______________ has a cubic crystal structure, in which one carbon atom is tetrahedrally bonded to four other carbon atoms⁴. This structure gives diamond its remarkable properties of luster, hardness, and thermal conductivity.  

Which of the following is not a part of John Dalton's Atomic Theory?

In an experiment, 7.0 g of nitrogen reacted with exactly 16.0 g of oxygen to form a single compound. What would be the total mass of the compound?

A 1.0-g sample of carbon dioxide (CO2) is fully decomposed into its elements, yielding 0.273 g of carbon and 0.727 g of oxygen. (a) What is the ratio of the mass of O to C?

A 1.0-g sample of carbon dioxide (CO2) is fully decomposed into its elements, yielding 0.273 g of carbon and 0.727 g of oxygen. (b) If a sample of a different compound decomposes into 0.429 g of carbon and 0.571 g of oxygen, what is its ratio of the mass of O to C?

Today we know that the atom is composed of

Particles with the same charge repel one another, whereas particles with opposite charges attract one another.

In an air sealed glass tube with a negative and positive end terminal, high voltage passes from the negative terminal (cathode) to the positive terminal (anode) and creates radiation which emits light. Their presence is detected only because they produce light in the tube (they fluoresce). What rays are produced as a result of the radiation in the tube, which are just streams of electrons moving across the tube?

On a battery, Cathode represents the negative charges (-), while anode represents the positive charge (+).

In a paper published in 1897, Thomson described cathode rays as streams of negatively charged particles that we now call _______________