Answer:
They are heavy metals.
Explanation:
Heavy metals are generally defined as metals with relatively high densities, atomic weights, or atomic numbers.
Answer:
diffraction
Explanation:
the correct answer is diffraction
Answer:
(d) burning a log.
(b) toasting a slice of bread;
Explanation:
Chemical change -
A chemical change refers to , the change in which a new compound is formed .
From the question ,
Its is not a chemical process , since no new compound is formed , these is only change in state as the liquid is turning to gaseous sate .
It is not a chemical process , as no new substance is formed .
- toasting a slice of bread
It is a chemical change , in which bread surface is deposited by a brown coat via the process of heating , even this process is a irreversible in nature .
It is a chemical change , as with the help of heating , the wood is turning to ashes .
OH- is common to bases.
Explanation:
The base is a is an ionic compounds which when placed in aqueous solution dissociates in to a cation and an anion OH-.
The presence of OH- in the solution shows that the solution is basic or alkaline.
From Bronsted and Lowry concept base is a molecule that accepts a proton for example in NaOH, Na is a proton donor and OH is the proton acceptor.
A base accepts hydrogen ion and the concentration of OH is always higher in base.
There is a presence of conjugate acid and conjugate base in the Bronsted and Lowry acid and base.
Conjugate acid is one which is formed when a base gained a proton.
Conjugate base is one which is formed when an acid looses a proton.
And from the Arrhenius base Theory, the base is one that dissociates in to water as OH-.
Answer:
The answer to your question is 0.41 moles
Explanation:
Data
moles of NaCl = ?
mass of NaCl = 24 g
Process
To solve this problem just calculate the molar mass of NaCl, and remember that the molar mass of any substance equals to 1 mol.
1.- Calculate the molar mass
NaCl = 23 + 35.5 = 58.5 g
2.- Use proportions and cross multiplication
58.5 g of NaCl ------------------- 1 mol
24.0 g ------------------- x
x = (24 x 1) / 58.5
x = 0.41 moles