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1 year ago

A cup of hot water loses 265 cal

Chemistry

1 answer:

elixir [45]1 year ago

7 0

Answer:

-1071 Joules

Explanation:

The Joule was introduced as the SI unit for energy in 1925. One calorie is equal to approximately 4.184 joules(J). This is a conversion factor that we can write two ways:

(1cal/4.184J) or (4.184J/1cal)

(265 cal)*(4.184J/1cal) = 1071 J

Since the energy is leaving the system, it should be written with a minus sign: -1071J

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Answer:

700N

Explanation:

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2 years ago

Atoms of element X weigh 32 times more than atoms of element Y. A compound has the formula: XY2 The ratio of the mass of X to th

tamaranim1 [39]

Answer:

16:1

Explanation:

Atoms of element X weigh 32 times more than atoms of element Y. We can write this in a symbolic way.

mX = 32 mY [1]

where,

mX and mY are the masses of X and Y, respectively

A compound has the formula: XY₂, that is, in 1 molecule of XY₂ there is 1 atom of X and 2 atoms of Y. The ratio of the mass of X to the mass of Y in this compound equals:

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2 years ago

calculate the standard potential arising from the reaction in which NADH is oxidized to NAD and the corresponding biological sta

melisa1 [442]

Answer:

-219.99kJ

Explanation:

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Also, the balanced equation for the reduction reaction is given below as:

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2 years ago

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Answer:

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