Which of the following laws is not explained by dalton’s atomic theory?

Which of the following laws is not explained by dalton’s atomic theory? a. the law of conservation of mass b. the periodic law c. the law of multiple proportions d. the law of definite proportions


B. The periodic law

The periods that make up the periodic table were conceived by Mendeleev in 1869, not Dalton

1. fewer valence electrons generally means more reactivity

2. law of conservation of energy – a

law of definite proportions – b

law of conservation of matter – c

3. In 1869 Russian chemist Dimitri Mendeleev started the development of the periodic table, arranging chemical elements by atomic mass. He predicted the discovery of other elements and left spaces open in his periodic table for them.

4.  Helium (He)  18  10 (2 electrons in outermost shell)The elements have full outermost shells and don’t tend to gain or lose electrons. They’re stable and don’t form compounds readily. They’re generally inert, or inactive. These are basically colorless gases that are abundant in the atmosphere.        

Inflating airships and balloons

Neon (Ne)   18  20 (8 electrons in outermost shell)  Used in electric lights

Argon (Ar)   18  30 (8 electrons in outermost shell)  Used to fill electric light bulbs and in welding  

Krypton (Kr)   18  40 (8 electrons in outermost shell)  Used in flashbulbs and strobe lights  

Xenon (Xe)   18  50 (8 electrons in outermost shell)  Used in flashbulbs and strobe lights  

Radon (Rn)1860 (8 electrons in outermost shell)  Used in certain medical treatments, can be environmental hazard

5 Fluorine (F)  17  2–1 (All halogens have seven electrons in their outer shells)      Pale yellow gas, penetrating odor; most active of all elementsPrevents decay of teeth, used in manufacturing


Chlorine (Cl)   173  Greenish-yellow gas, extremely poisonous and irritating; heavy, readily soluble in water, easily liquefied; forms chlorides with most metals  Used as a bleaching agent and disinfectant, used in water purification, used in manufacture of chlorine compounds; used to make salt (rock salt, seasoning), used in electrolysis, used to make HCl  

Bromine (Br)   17  4Reddish-brown liquid with suffocating odor  Used to make silver bromide used on photographic film, ingredient in an anti-knock constituent for gas  

Iodine (I)   17  5Purplish-black solid, boils at comparatively low temperatures, slightly soluble in water, unites with most metals and some nonmetals; sublimes  Used as a disinfectant for cuts and lacerations; important to nutrition

Astatine (At)  17  6Radioactive, occurs naturally but only in the smallest amounts  Only for scientific research, no practical industrial uses currently  

6. Hydrogen (H)  1  1  +1 (It has one valence electron)  Colorless, odorless, and tasteless; lightest substance known; burns with colorless flame; rarely found in free condition; mostly found in water, with other elements, in animal and vegetable matter, and in energy sources (petroleum, coal, natural gas)  Used industrially to form shortenings from animal and vegetable oils and to produce ammonia  

Carbon (C)  142  +4/–4 (It has four valence electrons)  Exists as diamond, graphite, or an amorphous form with various properties; as carbon monoxide, it’s colorless, odorless, tasteless, and poisonous; as carbon dioxide, it’s a colorless gas that is a product of fuel combustion, respiration, and decay or living matter  As a diamond, it’s used for cutting and industrial purposes; as graphite, it’s used in pencils, making melting pots, used as a lubricant and in industry; as an amorphous material, it’s used as fuel and as a coloring material; CO2 is used in making fire extinguishers, washing soda, and in manufacture of dry ice  

7. Water is colorless, odorless, and tasteless. It’s the chief substance of living material. It has a specific gravity of 1.0 at 4° Celsius. It freezes at 0° Celsius and boils at 100° Celsius. Water is a powerful solvent. Distillation is needed to remove impurities. Purification methods include

Aeration (water is sprayed into the air so that light and oxygen can kill bacteria)

Filtration (water is passed through a filter to remove impurities)

Chlorination (chlorine is added to water to destroy bacteria)

Coagulation (chemicals are added to water to cause organic matter with bacteria

to settle out)

8. Air contains nitrogen (78%), oxygen (21%), carbon dioxide (0.04%), and rare gases (less than 1%). It also contains water, dust, bacteria, and other materials.

explaination YeS

answer: The law of definite proportions


B. the periodic law


The periodic law was not explained by the Dalton’s atomic theory.

The periodic law was first postulated by Dimitry Mendeleef and Lothar Meyer around 1869 where they independently arrived at the periodic table or chart.

The table was based on the periodic law which states that “chemical properties of elements are a periodic function of their atomic weights”. The modern periodic law was restated by Henry Moseley in the early 1900s. He changed the basis of the law to atomic number. The present periodic law is stated as “the properties of elements are a periodic function of their atomic number”.

The laws of conservation of mass, multiple proportions and definite proportions are all explained by the Dalton’s atomic theory.

learn more:

Dalton’s model of the atom


The answer are: a. the law of definite composition; b. the law of conservation of mass; d. the law of multiple proportions


Dalton based his atomic theory on two laws: the law of conservation of mass and the law of definite composition.

The law of conservation of mass says that in a closed system, matter is not created or destroyed. For example, if there is a chemical reaction, the amount of each element of that reaction is the same in the reagents and in the products. While the law of defined composition says that a pure compound will have the same proportion of the elements that make it up. An example, salt, which has a chemical formula NaCl, has the same proportion of sodium and chlorine.

The law of multiple proportions, when two elements come together in different proportions to create different compounds, this means that their atoms come together in different numerical relationships. For example, if an atom of an element A joins with two atoms of element B, the weight ratio of the quantities that bind are in a ratio of 1: 2.

The answer to your question is letter c) 6.09 g of sodium and 9.38 g of chlorine.


This problem is solve using rule of three

We know that the proportion Sodium to Chloride is 1 to 1 in sodium chloride, so we have to look for this proportion in the options

AM Sodium = 23 g

AM Chlorine = 35.5 g

                 Sodium                                     Chlorine

           23 g 1 mol              35.5 g 1 mol

       1713.73g    x               2666.6 g    x

          x = 1713.73/23 = 74.51                     x = 2666.6/35.5 = 75.12

    These values are very similar, we have to look for the proportion in the options

a)      6.09g of sodium = 0.26 mol

      4,87 g of chlorine = 0.14 mol           These numbers are not very similar

b) We have 0.26 mol of Na

                  0.037 mol of Cl                      This is not the answer

c) We have 0.26 mol of Na

                  0.26 mol of Cl                     These numbers are the same, the proportion is 1:1, this is the answer

d) We have 0.26 mol of Na

                   0.36 mol of Cl                    This is not the answer

The correct answer is b) 4.17 g of sodium and 6.42 g of chlorine


According to the law of definite proportions a chemical compound is composed always by the same elements in the same proportions by mass. In this case, the proportion of the elements by mass will be 4.37 g of chlorine (Cl) per 2.84 g of sodium (Na):

4.37 Cl/2.84 g Na= 1.54

We can calculate the proportions of the results in order to see which is the correct:

a) 3.75 g Cl/4.17 g Na = 0.899

b) 6.42 g Cl/4.17 g Na = 1.539 ⇒ ≅1.54

c) 1.05 g Cl/4.17 g Na = 3.971

d) 12.1 g Cl/4.17 g Na = 2.901

The option in which the proportion Cl/Na is equal to 1.54 is option b

The correct answer is b. Law of Definite Composition.

Further Explanation

A) Law of Conservation of Mass

FALSE. This law describes the masses of substances before and after a reaction as constant. Atoms only rearrange in during chemical reactions. None is destroyed nor are any new atoms created. Therefore, the total mass of reactants must always be equal to the total mass of the products.

B) Law of Definite Composition

TRUE. Sometimes called the Law of Constant Composition, this law states that regardless of the source of a compound, its composition is the same. The mass percentages of the elements that make up a particular compound is constant. KCl, in the example, will always have 1 mol of potassium ions and 1 mole of chloride per mole of the potassium chloride regardless of whether it was from Chile or Poland.

C) Law of Multiple Proportion

FALSE. This law describes how an element combines with another element to form multiple compounds. The ratio at which they combine are in whole numbers.

D) Law of Conservation of Mass and Definite Composition

FALSE. The Law of Conservation of Mass pertains to what happens to masses  of substances before and after a chemical reaction. This problem is about different sources of a compound and not about a specified chemical reaction.

E) Law of Conservation of Mass and Multiple Proportions

FALSE. The problem is about the mass percentage of compounds from different sources, not about the reaction of the compound nor other compounds formed by potassium and iodine.

Learn MoreBalancing Equations Mass Percentage

Keywords: Law of Definite Proportion, Law of Constant Composition

The number of valence electrons that an atom has dictates its ability to react chemically. The closer an atom is to achieving a full outermost shell, the more likely it will be to borrow electrons. Atoms are paired in a way that allows both to achieve a full stable outermost shell. For example, one atom of silicon has 14 electrons, four of which are valence electrons in the outermost shell. Silicon can lend, share, or gain four electrons to achieve a full outermost shell.

a. Law of conservation of energy

b. Law of definite proportions

c. Law of conservation of matter

Mendeleev first published a table of elements arranged according to increasing atomic masses. He noticed that some elements near each other had differing properties, but elements in vertical columns had similar properties. Moseley then rearranged the table according to atomic numbers and this eliminated the discrepancies found in Mendeleev’s attempt. Today’s version of the periodic table displays elements in order based on their atomic number; the atomic number indicates the number of protons within the atoms of a particular element. Rows are called periods and columns are called groups. Elements in the same group have similar properties. Elements are grouped into nine categories: noble gases, halogens, nonmetals, alkali metals, alkaline earth metals, transition metals, other metals, metalloids, and rare earth elements.


penn foster

A chemical compound always contains its component element in a fixed ratio.

Leave a Reply

Your email address will not be published. Required fields are marked *