Dalton's atomic theory explained the observation that the percentage by mass of the elements in a compound is always the same, thus dalton's atomic theory supports what law? a. the law of definite composition b. the law of conservation of mass c. the law of conservation of energy d. the law of multiple proportions e. the law of chemical compounds

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

Explanation:

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.

> b takes place in the gas phase in an isothermal tubular reactor. the feed is one mole of a per one mole of c, an inert. the entering temperature and pressure are 427°c and 10 atm, respectively. the gas constant r = 0.08206 atm · l/mol · k.

a). in this case, dh> 0 and sd> 0. if t becomes larger, the term "-tds" will become more negative. at some point, it is possible that -dts will be more negative than the dh is positive, and the reaction will become spontaneous. this is probably the correct answer, but you should look at all of the other possibilities and make sure of that.