Answer:
length
Explanation:
The metre is defined as the length of the path travelled by light in a vacuum in 1299 792 458 of a second. The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole – as a result the Earth's circumference is approximately 40,000 km today.
Answer: single replacement reaction, 
Explanation:
A single replacement reaction is one in which a more reactive element displaces a less reactive element from its salt solution.
A general single displacement reaction can be represented as :
As strontium metal is added to aluminum chlorate , strontium being more reactive than aluminium, displaces aluminium atom its salt solution and lead to formation of strontium chlorate and aluminum metal.
Answer:
Explanation:
a ) period 4 noble gas is krypton
isoelectronic with it are Sr ⁺² and Br⁻
compound is SrBr₂
b ) Period 3 noble gas is Argon
isoelectronic with it are Mg⁺² and O⁻²
compound is MgO
c) 2+ ion is the smallest with a filled d subshell is Zn⁺² , smallest halogen
is F⁻
compound is ZnF₂
d ) ions from the largest and smallest ionizable atoms in Period 2
Li⁺ and F⁻
compound is LiF
