3 10.0 grams of granite is heated from 30 °C to 50 °C . How much energy does this require? The specific heat of granite is 0.79J/goC

The energy required is 158 J

Explanation:

Calorimetry is the measurement and calculation of the amounts of heat exchanged by a body or a system.

When the heat added or removed from a substance causes a change in temperature in it without affecting its molecular structure, this heat is called sensible heat.

In other words, when a system absorbs (or gives up) a certain amount of heat, it can happen that it experiences a change in its temperature, which implies sensible heat.

The equation that allows calculating heat exchanges is:

Q = c * m * ΔT

where Q is the heat exchanged by a body of mass m, made up of a specific heat substance c and where ΔT is the temperature variation.

In this case:

Replacing:

Q= 0.79 *10 g* 20 C

Solving:

Q= 158 J

The energy required is 158 J

c. heat could easily travel through the molecules in the air and escape/enter the flask. removing the air slows down the heat transfer.  

answer:

the answer is 6 valence electrons.

explanation:

valence is the # of electrons on the outer most shell of an atom.

oxygen has 6.

although, the valency of oxygen is 2, because it only needs to make 2 covalent bonds, or gain 2 electrons, to achieve the stable octet configuration of a noble gas.

that's it!

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