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1 year ago

How much heat in Joules is needed for an increase in temperature by 12.5 degrees of an 8 gram block of gold

Chemistry

1 answer:

Vinil7 [7]1 year ago

4 0

Answer: 13

Explanation:

$Q=mc \Delta T\\\\Q=(8)(0.13)(12.5)\\\\Q=\boxed{13}$

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Can some tell me plz

valentina_108 [34]

Answer: stay the same because it's a solid.

Explanation:

5 0

2 years ago

Read 2 more answers

The metallic radius of a potassium atom is 231 pm. What is the volume of a potassium atom in cubic meters?

Sauron [17]

1 pm = 10∧-10 cm
Therefore, 230 pm is equivalent to 2.3 ×10∧-8 cm.
Atom is in the shape of a sphere,
The volume of a sphere is given by 4/3πr³
Thus, volume of the atom = 4/3π( 2.3 ×10∧-8)³
= 4/3 (3.142 ×12.167×10∧-24
= 5.096 ×10∧-23 cm³
but 1m³= 1000000cm³
Therefore, the volume of the atom = 5.096 ×10∧-29 m³

8 0

3 years ago

What is the mass sample of 0.0500 moles of zinc chloride ?

vlabodo [156]

Answer:

6.82g

0.59moles

Explanation:

1. What is the mass sample of 0.0500 moles of zinc chloride ?

Given parameters:

Number of moles ZnCl₂ = 0.05moles

Unknown:

Mass of the sample = ?

Solution:

To find the mass of a substance using the number of moles, it would be pertinent to understand what mole is.

A mole is a substance that contains the avogadro's number of particles.

It relates to the mass using the expression below;

Mass of a substance = number of moles x molar mass

Molar mass of ZnCl₂;

Atomic mass of Zn = 65.4g/mol

Cl = 35.5g/mol

Molar mass = 65.4 + 2(35.5) = 136.4g/mole

Mass of a substance = 0.05 x 136.4 = 6.82g

2. How many moles of potassium sulfide are in a 65.50g sample?

Given parameters:

Mass of K₂S = 65.5g

Unknown:

Number of moles = ?

Solution:

The number of moles of any substance is related to mass using the expression below;

Number of moles = $\frac{mass}{molar mass}$

Molar mass of K₂S = 2(39) + 32 = 110g/mol

Number of moles = $\frac{65.5}{110}$ = 0.59moles

8 0

3 years ago

Exactly 1.0 mol N2O4 is placed in an empty 1.0-L container and is allowed to reach equilibriumdescribed by the equation N2O4(g)↔

Vilka [71]

Answer : The correct option is, (C) 1.1

Solution : Given,

Initial moles of $N_2O_4$ = 1.0 mole

Initial volume of solution = 1.0 L

First we have to calculate the concentration $N_2O_4$ .

$\text{Concentration of }N_2O_4=\frac{\text{Moles of }N_2O_4}{\text{Volume of solution}}$

$\text{Concentration of }N_2O_4=\frac{1.0moles}{1.0L}=1.0M$

The given equilibrium reaction is,

$N_2O_4(g)\rightleftharpoons 2NO_2(g)$

Initially c 0

At equilibrium $(c-c\alpha)$ $2c\alpha$

The expression of $K_c$ will be,

$K_c=\frac{[NO_2]^2}{[N_2O_4]}$

$K_c=\frac{(2c\alpha)^2}{(c-c\alpha)}$

where,

$\alpha$ = degree of dissociation = 40 % = 0.4

Now put all the given values in the above expression, we get:

$K_c=\frac{(2c\alpha)^2}{(c-c\alpha)}$

$K_c=\frac{(2\times 1\times 0.4)^2}{(1-1\times 0.4)}$

$K_c=1.066\aprrox 1.1$

Therefore, the value of equilibrium constant for this reaction is, 1.1

4 0

2 years ago

Active

klio [65]

Option B

Primary productivity is not limited by time

<u>Explanation:</u>

To ecosystems, the productivity of the primary producers is essential because certain bodies generate energy for different existence bodies. Besides the era, primary production ends in the extension of dissimilar plant biomass to the practice. Consumers acquire their strength from primary producers, unless directly (herbivores, any detritivores), or diffusely.

It depends superimposed on the availability of the sunlight, availability of the nutrients such as nitrogen, iron, phosphorus from the soil and water. The primary productivity of the plant's distinct autotrophs is not restricted by time.

5 0

3 years ago