Answer:
decomposition reaction.
Explanation:
It is a decomposition reaction as potassium chlorate compound breaks to form potassium chloride and oxygen. This reaction requires heat as source of energy to break down the compound so it is endothermic in nature.
Answer:
Elements having same valence electrons are placed in <u>same group.</u>
Explanation:
First, let's start with some basic concepts of modern periodic table:
1. Modern Periodic table : It is the arrangement of element in the increasing order of their atomic numbers
The Modern periodic table is divided into Periods and groups .
Periods : These are the horizontal rows. There are seven periods in the periodic table . Period 1 has 2 element. Period two and three has 8 elements , period 4 and 5 have 18 elements and the period 6 and 7 have 32 elements.
Same period have same number of atomic orbital(Shell)
Group : The group is the vertical columns . There are 18 groups in the modern periodic table.Those element which have same group number will also have same number of electron in their outermost shell. The number of electron in the outermost shell determines the valency of the element.
So, elements showing same valency are placed in same group.
All alkali are place in group 1 and have 1 valance electron in the outermost shell
Answer: O potássio possui apenas um elétron de valência. ... Considerando que o cálcio possui dois elétrons de valência, requer mais energia para a remoção de um elétron de valência. Devido a esse potássio, é mais reativo que o cálcio.
Explanation:
Answer:
Model D
Explanation:
Bohr's Model has a planetary look. Where the electrons are in an orbit.
Answer:
The answer to your question is letter C.
Explanation:
Reaction
Potassium hydroxide = KOH
Barium chloride = BaCl₂
Potassium chloride = KCl
Barium hydroxide = Ba(OH)₂
KOH + BaCl₂ ⇒ KCl + Ba(OH)₂
Reactant Elements Products
1 K 1
1 Ba 1
2 Cl 1
1 H 2
1 O 2
The reaction is unbalanced
2KOH + BaCl₂ ⇒ 2KCl + Ba(OH)₂
Reactant Elements Products
2 K 2
1 Ba 1
2 Cl 2
2 H 2
2 O 2
Now, the reaction is balanced
