Answer:
<em>In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.</em>
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I HOPE THIS WILL HELP YOU IF NOT THEN SORRY HAVE A GREAT DAY:)</h3>
Convection is when cool air sinks and warm air rises. i am not 100% sure though
• Bubbles of a colourless, odourless gas are evolved
• The solution turns red litmus blue
Ca + 2H_2O→ Ca(OH)_2 + H_2
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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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Equation of decomposition of ammonia:
N2+3H2->2NH3
Euilibrium constant:
Kc=(NH3)^2/((N2)((H2)^3))
As concentration of N2=0.000105, H2=0.0000542
so equation will become:
3.7=(NH3)^2/(0.000105)*(0.0000542)^3
NH3=√(3.7*0.000105*(0.0000542)^3)
NH3=7.8×10⁻⁹
So concentration of ammonia will be 7.8×10⁻⁹.