Because their molecules are more tightly packed. Massdensity = ---------- Volume
So more densely packed molecules means more mass per unit volume. Hence metals are denser than non-metals.
Hi, here is a basic summary of what we did in a lab; there were 3 reactions: The procedure: Reaction 1: Solid sodium hydroxide dissolves in water to form an aqueous solution of ions. NaOH(s)-> Na+(aq) + OH-(aq) ΔH1=-34.121kJ Reaction 2: Solid sodium hydroxide reacts with an aqueous solution of HCl to form water and an aqueous solution of sodium chloride. NaOH(s) + H+(aq) + Cl-(aq) -> H2O + Na+(aq) + Cl-(aq) ΔH2=-83.602kJ Reaction 3: An aqueous solution of sodium hydroxide reacts with an aqueous solution of HCl to form water an an aqueous solution of sodium chloride. H+(aq) + OH-(aq) + Na+(aq) + Cl-(aq) -> H2O + Na+(aq) + Cl-(aq) ΔH3= -50.2kJ The ΔH values were calculated by dividing the heat gained by the number of moles (each reaction had 0.05moles of NaOH) The problem: Net ionic equations for reaction 2 & 3: 2: NaOH(s) + H+(aq) -> H2O + Na+(aq) 3: H+(aq) + OH-(aq) -> H2O i) In reaction 1, ΔH1 represents the heat evolved as solid NaOH dissolves. Look at the net ionic equations for reactions 2 and 3 and make similar statements as to what ΔH2 and ΔH3 represent. ii) Compare ΔH2 with (ΔH1 + ΔH3). Explain in sentences the similarity between these two values by using your answer to #5 above. Attempt at answering: i) Firstly, ΔH2 represents the heat evolved as the hydrogen ion displaces the sodium ion, creating a single displacement reaction. ΔH3 represents the heat evolved as the hydrogen and hydroxide ion form water via a neutralization reaction. ii) ΔH2 is equal to (or supposed to be, this is a source of error while calculating) (ΔH1 + ΔH3). The similarity between these two values is that .. (this is where I get confused!)
Source https://www.physicsforums.com/threads/calorimetry-help-chemistry.399653/
John Dalton made some hypothesis about the structure of atom. He proposed that matter is composed of great number of indivisible particles called atoms they can neither be destroyed nor be created.
<h3>What is atomic theory?</h3>
There are different theories regarding the structure and electronic properties of an atom. Many scientists contributed to the modern theory of atomic structure in which John Dalton was first to mention the word atom.
According to Dalton' theory, matter is composed of indivisible particles called atoms. Atoms can neither be created nor be destroyed. All the atoms of the same element are identical in all aspects.
Atoms of different elements are different and the compounds are formed by the combination of atoms. Dalton's theory provided a sound basis for the laws of chemical combination and also several properties of gases and liquids known at that time.
However, he could not explain the reason for chemical combination of atoms and did not give any idea about the existence of isotopes and isobars.
Hence, the main aspects of Dalton's theory was the indivisibility of atoms and the chances of chemical combination.
To learn more about Dalton's theory, find the link below:
brainly.com/question/11855975
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Answer:
-OH
Explanation:
Alcohols generally have the structural formula OH
for example, ethanols structural formula is C2H5OH
Answer:
While Bohr's atomic model hypothesizes that electrons move in particular energy levels around the nucleus, the electron cloud model suggests that electrons move in an unpredictable pattern but are more likely to be in certain regions than others.
