Can someone help me solve all of these problems? (Will give brainliest and a heart)

4. Why do elements in the same family generally have similar properties?

snow_tiger [21]

Because they have the same number of electrons in the outer shell, they have the same reactivity (they all want to lose/gain a certain amount of electrons to have a full shell of 8), so they have the similar melting, boiling points etc because they all undergo very similar reactions to certain factors so have similar outcomes

7 0

4 years ago

How much heat is needed to melt 100.0 grams of ice that is already at 0°C?

Jet001 [13]

Taking into account the definition of calorimetry and latent heat, the heat needed to melt 100.0 grams of ice that is already at 0°C is 33,400 J (option A).

<h3>Calorimetry</h3>

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

<h3>Latent heat</h3>

Latent heat is defined as the energy required by a quantity of substance to change state.

When this change consists of changing from a solid to a liquid phase, it is called heat of fusion and when the change occurs from a liquid to a gaseous state, it is called heat of vaporization.

In this case, the heat Q that is necessary to provide for a mass m of a certain substance to change phase is equal to

Q = m×L

where L is called the latent heat of the substance and depends on the type of phase change.

<h3>Heat needed to melt ice</h3>

In this case, you have to melt the ice into liquid water.Being the specific heat of melting of ice is 334 J/g, the heat needed to melt 100 grams of ice is calculated as:

Q= 100 grams× 334 J/g

Solving:

In summary, the heat needed to melt 100.0 grams of ice that is already at 0°C is 33,400 J (option A).

Learn more about calorimetry:

brainly.com/question/15224761

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4 0

1 year ago

What is the formula for heat of fusion?

spin [16.1K]

Answer:

The formula used to calculate heat of fusion:

q = m·ΔH f

Explanation:

The formula used to calculate heat of fusion:

q = m·ΔH f

8 0

3 years ago

Read 2 more answers

If 2.76 g of CuNO3 is dissolved in water to make a 0.350 M solution, what is the volume of the solution?

Licemer1 [7]

I can't remember any of the weights of the individual elements but here is how you solve it:
Molecular weight of copper + nitrogen + 3 oxygens = molecular weight of the compound.
M = moles / liter
.350 moles / 1 liter
Do .350 moles / liter x the molecular weight (g / mole) of the compound = the answer in g / L

5 0

3 years ago

Why is respiration an exothermic reaction?

Degger [83]

Answer: A large amount of energy is released into the surroundings.

Explanation:-

Endothermic reactions are defined as the reactions in which energy of the product is greater than the energy of the reactants. The total energy is absorbed in the form of heat and $\Delta H$ which is difference between energy of products and energy of reactants come out to be positive.

Exothermic reactions are defined as the reactions in which energy of the product is lesser than the energy of the reactants. The total energy is released in the form of heat and $\Delta H$ which is difference between energy of products and energy of reactants comes out to be negative.

Thus a reaction in which large amount of energy is released is categorized as exothermic reaction and thus respiration is also a exothermic reaction.

7 0

3 years ago