Answer:
2Mg (s) + 
(g) ---> 2MgO (s)
Explanation:
The on that is considered a physical change is : A. Sawing a piece of wood in half
When you cut a piece of wood, the chemical compound within the wood will not change at all, which mean that it's a physical change
hope this helps
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:
because hard water is salty
What is the average velocity of atoms in 1.00 mol of argon (a monatomic gas) at 275 k for m, use 0.0399kg
Answer: The average velocity of the atoms 847.33 m/s.
Explanation:
Moles of the neon = 1.00
Temperature of the gas : 288 K
Mass of the gas = 0.01000
R = 8.31 J/mol K
The average velocity of the atoms 847.33 m/s.
