The correct answer is option 1. Be, Mg, and Ca is the correct order arranged in increasing atomic radius. This is predicted based on the periodic table. The atomic sizes increases as one moves downwards in the periodic table.
So to balance an equation, you need to get the same amount of each type of element on either side of the --> . So you pretty much are given the subscripts in the equations and you need to add coefficients (just normal numbers) in front of any formula that needs it, keeping anything balance.

turns into

These coefficient numbers are the molar ratios, so 2 moles of KCl3 for every 3 moles of O2 so 1. 3:2
Then you can use these ratios of find out how many moles of one thing are needed if you are given the amount of another.

and use cross multiplication to solve for whatever you don't know
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Answer : The correct option is, Malleable, shiny, and able to conduct heat or electricity.
Explanation:
Metals : Metals are the elements which can easily loose electrons and forms cations.
Properties of metals :
- They are lustrous (shine).
- They are malleable and ductile (flexible).
- They conduct heat and electricity.
- The metallic oxides are basic in nature.
- They form cations in an aqueous solution.
Non-metals : Non-metals are the elements which can easily gain electrons and form an anion.
Properties of non-metals :
- They are non-lustrous.
- They are brittle and hard in nature.
- They do not conduct heat and electricity.
- The non-metallic oxides are acidic in nature.
- They form anions in an aqueous solution.
Hence, from the given options the correct option for metal is, Malleable, shiny, and able to conduct heat or electricity.
2:7 ratio of ethane to O2 = 15:x 9solve for x)
x=52.5 mol O2
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Answer: Option B</h2>
Option A is incorrect. <u>Heated water cannot freeze.</u>
Option B is correct. <u>Heated water will evaporate.</u>
Option C is incorrect. <u>Heated water cannot create condensation.</u>
Option D is incorrect. <u>Water can't melt when heated unless it's been frozen beforehand. </u>
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