Answer:
Josue
Explanation:
J.J Thompson proposed the plum pudding model of the atom. In his proposition, the atom is a sphere of positive charges into which negative charges were embedded. This model of the atom did not significantly contribute to our present day understanding of atomic structure.
On the other hand Ernest Rutherford laid out the foundation for a more accurate understanding of atomic structure in his nuclear model of the atom. According to Rutherford, the atom consists of a positively charged massive core called the nucleus around which electron move in orbits. His idea was akin to the solar system with the sun at it's core and planets moving around the sun in orbits.
This his idea of the nuclear theory was held as fundamentally correct by Neils Bohr's model of the atom. Hence, his nuclear theory of the atom was a significant milestone in our present day understanding of atomic structure.
Answer: No
Explanation:
- Law of definite proportions is a case from the Law of conservation of energy (matter) which states that "mass can neither be created nor destroyed, but changed from one form to another."
- Adding coefficients to a chemical equation confirms that there is the same number of atoms on both sides of a reaction; therefore, matter has not been created or destroyed but reorganized to give new substrates.
Example : 2 Mg + O2 → 2 MgO
In the balanced equation above, 2 moles of Mg reacts with 1 mole of O2 to produce 2 moles of MgO.
mass of 2 moles of Mg = 24×2= 48 grams
mass of 1 mole of O2 = 16+16 = 32 grams
total mass of reactants = 48 + 32 = 80 grams
mass of 2 moles of MgO = (24+16) ×2 = 80 grams
total mass of products = 80 grams
It is clear that the number of grams of matter before and after the reaction is the same and equals to 80 grams, so obeys the law of definite proportions..
Answer:
Synthesis reaction
Explanation:
This is a synthesis reaction. When you combine sodium metal (Na) with chlorine gas (Cl), you form sodium chloride or kosher salt (NaCl).
<em>Hope this explanation helps!</em>
Explanation:
a chemical reaction in which the rate of reaction is proportional to the concentration of each of three reacting molecules
Answer:
Explanation:
Titration is a method used to determine the concentration of a substance. The formula for this is:
Where M is the molarity of the acid or base and V is the volume of the acid or base.
We know that 46.0 milliliters of a 0.15 molar solution of nitric acid wereused in the titration. 25.0 milliliters of solution of calcium hydroxide of unknown molarity were also used.
Substitute these known values into the formula.
We are solving for the molarity of the base, so we must isolate the variable 
. It is being multiplied by 25.0 milliliters. The inverse operation of multiplication is division, so we divide both sides of the equation by 25.0 mL.
The units of milliliters (mL) cancel.
The original measurements have 2 or 3 significant figures. We always round our answer to the least number of sig figs, which is 2. For the number we calculated, that is the hundredths place. The 6 in the thousandths place tells us to round the 7 up to an 8.
The concentration of calcium hydroxide is approximately <u>0.28 M.</u>
