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when a substance is boiled, what happens to the mass?

the mass increases as it changes from a liquid to a gas.
the mass stays constant as it changes from a liquid to a gas.
there is no mass once the substance becomes a gas.
the mass decreases as it changes from a liquid to a gas.

The mass stays constant as a substance changes from a liquid to a gas.  

The Law of Conservation of Mass states that, in ordinary chemical reactions, mass is neither destroyed nor created.

That is, the mass of the reactants must equal the mass of the products.

2H₂O(ℓ) ⟶ 2H₂O(g)

   1 g              1 g

If the mass of liquid water is 1 g, the mass of the water vapour must be 1 g.

Even though the water vapour is a gas and you can’t see it, it still has a mass

of 1 g.

"you start with 15.67 g mgco3-xh2o, when heated and all the water is removed, you are left with 7.58 g mgco3 only.

therefore, you had 15.67 - 7.58 = 8.09g h2o  

moles of each :

7.58g mgco3 = ? moles = 7.58g / 83.4g/mole = 0.09moles  

8 09g h2o = ? moles = 8.09g / 18g/mole = 0.44moles  

molar ratio between the two by dividing both numbers by the smallest number :

0.09 / 0.09 = 1  

0.44 / 0.09 = 4.8  

mgco3-5h2o"

question: ray weighs 100 kilograms, his wrestling partner, bobby, weighs 50 kilograms. if ray moves at 4 m s , how fast will bobby have to run at him to apply an equal amount of kinetic energy?

answer: 8 m/s he needs to run twice as fast to keep up so he has some work to do

explanation:   if the mass has units of kilograms and the velocity of meters per second, the kinetic energy has units of kilograms-meters squared per second squared.

question answered by

(jacemorris04)