Answer: Elements in Group 2
Explanation: The periodic table was arranged by Dmitri Mendeleev specifically around similarites in their chemical behaviors. He found that as atomic number increases, at some point an element starts to react in a manner similar to a previous one. When that happened, he would place the larger element under the smaller one, and eventually noticed a periodicity in the table. Elements in a column (Groups) had similiar chemical properties. We know today that these similarities are due to the electron configuration, and that these configurations repeat themselves. He left gaps in the table when he could find an existing element with properties similar to others in that group. I big leap of faith, but it worked. Elements for those missing boxes were eventually discovered.
Molar mass ethanol:
C2H5OH = 12 x 2+ 1 x 5 + 16 + 1 = 46.0 g/mol
volume = 545 mL in liters: 545 / 1000 => 0.545 L
number of moles:
29.0 / 46.0 => 0.6304 moles
M = n / V
M = 0.6304 / 0.545
M = 1.156 mol/L
hope this helps!
Answer:
Coefficient of 
Coefficient of 
=8
Explanation:
We are given that a reaction in which 
reacts with
We have to find the coefficient of each reactants in balanced reaction
Coefficient is defined the constant value multiplied with a reactant in a reaction.
Coefficient of =3
Coefficient of 
Coefficient of 
Coefficient of 
Coefficient of 
Coefficient of KOH=2
Hence, Coefficient of and coefficient of
Pure substances are substances<span> that are made of only one type of atom or molecule....</span>
Answer:
Explanation:
During titration indicators are often used to identify chemical changes between reacting species.
For colorless solutions in which no noticeable changes can easily be seen, indicators are the best bet. Most titration processes involves a combination of acids and bases to an end point.
Indicators are substances whose color changes to signal the end of an acid-base reaction. Examples are methyl orange, methyl red, phenolphthalein, litmus, cresol red, cresol green, alizarin R3, bromothymol blue and congo red.
Most of these indicators have various colors when chemical changes occur.
Also, there are heat changes that accompanies most of these reactions. These are also indicators of chemical changes.
