D. this is the correct answer because the question is showing a comparison of sizes rather than the actual sizes which eliminates B. A and C have no relevance.
Answer:
Democritus
Explanation:
Democritus was a Greek philosopher that first conceptualize the idea of an atom. He suggested matter to be composed of atoms, which move through empty spaces. Democritus explained that different kinds of atoms have different sizes and shapes.
His proposition was not made into a theory by the scientific community of that time because there was barely little to no evidence to support the findings. The technology as a that time were not sophisticated to back up these claims.
Answer:
Mass = 36.38 g
Explanation:
Given data:
Mass of hydrogen = 30.0 g
Mass of nitrogen = 30.0 g
Theoretical yield of reaction = ?
Mass of ammonia = ?
Chemical equation:
N₂+ 3H₂ → 2NH₃
Number of moles of N₂:
Number of moles = Mass /molar mass
Number of moles = 30 g / 28 g/mol
Number of moles = 1.07 mol
Number of moles of H₂:
Number of moles = Mass /molar mass
Number of moles = 30 g / 2g/mol
Number of moles = 15 mol
Now we will compare the moles of NH₃ with hydrogen and nitrogen .
H₂ : NH₃
3 : 2
15 : 2/3×15= 10 mol
N₂ : NH₃
1 : 2
1.07 : 2 × 1.07= 2.14 mol
The number of moles of NH₃ produced by nitrogen are less it will be limiting reactant.
Mass of ammonia:
Mass of NH₃ = moles × molar mass
Mass =2.14 mol × 17 g/mol
Mass = 36.38 g
Explanation:
4. limestone heat lime + carbon dioxide
The reactants in this expression above is limestone
The products of the reaction is carbon dioxide and lime
Reactant is the species that gives the product and it is usually found on the left hand side of the expression.
The product is the substance on the right hand side of the expression that forms through the experiment.
Heat is used to facilitate the reaction.
5. An exothermic reaction is a reaction in which heat is given off.
An endothermic reaction is a reaction in which heat is absorbed in the process.
An exothermic reaction is always warmer after the reaction whereas an endothermic reaction is colder at the end of the reaction.
6. Sodium salicylate is made from carbon dioxide and sodium phenoxide.
The reactants are:
Carbon dioxide and sodium phenoxide
The product is:
Sodium salicylate