Answer:
Henry Moseley
Explanation:
Dmitry Mendeleef and Lothar Meyer proposed a periodic table based on the atomic mass.
They stated a periodic law expressed as "chemical properties of elements are a periodic function of their atomic weights".
But, Henry Moseley in 1900s re-stated periodic law by changing the basis of the law from atomic weight to atomic number.
The present periodic law is stated as "the properties of elements are a periodic function of their atomic number".
Answer:
single replacement
Explanation:
Step 1: Data given
single replacement = A reaction in which one element replaces a similar element in a compound. For example, a metal replaces an other metal.
The general form of a single-replacement (also called single-displacement) reaction is:
A+BC→AC+B
Decomposition = a reaction in which a compound breaks down into two or more simpler substances. The general form of a decomposition reaction is:
AB→A+B
Synthesis = A reaction that occurs when one or more compounds combines to form a complex compound:
A + B → AB
Double replacement: a reaction in which the positive and negative ions of two ionic compounds exchange places to form two new compounds.
The general form of a double-replacement reaction is:
AB+CD→AD+BC
Combustion reaction = a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat. Combustion reactions must involve O2 as one reactant.
The reaction Zn + 2HCl → ZnCl2 + H2
⇒ Does not involve O2 = NOT a combustion reaction
⇒ The compounds do not form a complex compound = NOT a synthesis
⇒ A compound does not break down into smaller substances = NOT a decomposition
⇒ There is a replacement between Zn and H. This is a <u>single replacement</u>, not a double replacement reaction.
Answer:
a) 1 x 10^-11 mol/L
b) 1 x 10^-6 mol/L
c) 1 x 10^-5 fewer H+ ions
Explanation
pH stands for Power of Hydrogen, the more acidic a substance is, the more H+ ions it has rendering the substance acidic. a pH of 1 means the concentration of H+ ions is 1 x 10^-1. A pH of 7 means the concentration of H+ ions is 1 x 10^-7 and so on.
10^-11 has 10^-5 more H+ ions than 10^-6
Hope this helps :)
Answer:
325
Explanation:
velocity = 3250 Hz x 0.1 m
