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Kazeer [188]
3 years ago
15

Which elements make up 95 percent (by weight) of the human body?

Chemistry
1 answer:
Alex17521 [72]3 years ago
3 0
Oxygen,carbon,hydrogen,and nitrogen- together make up 95 percent of the mass of the human body.
Hope this helps.
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Explanation:

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Calculate the molarity of a KCl solution if 37.3 g of KCl are dissolved in water to give a
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The rate constant for a reaction is 4.65 L mol-1s-1. What is the overall order of the reaction? zero
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units of reaction and their order.

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When a chemical reaction is run in aqueous solution inside a calorimeter, the temperature change of the water (and Ccal) can be
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Answer:

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Explanation:

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HCl + NaOH → NaCl + H₂O

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Moles of NaOH  = 50.mL × 1.00 M = 50.0 mmol = 0.0500 mol

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so we substitute

q_soln = (100g × 4.18 × ( 28.0 °C - 21.2 °C) ) + 1234.28

q_soln = 2842.4 + 1234.28

q_soln = 4076.68 J

Enthalpy change for the neutralization is ΔH_{neutralization}

ΔH_{neutralization} = -q_soln / mole of water produced

so we substitute

ΔH_{neutralization} = -( 4076.68 J ) / 0.0500 mol  

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