What do these two changes have in common?

Valentin [98]

Answer:

South American

Explanation:

When you look at a map of plates, only South American forms a boundary with the African plate out of those specific plates

6 0

3 years ago

Read 2 more answers

Which of the following statements does not describe what he structure of an atom an atom has a small dense center called nucleus

nikklg [1K]

Answer:

inside the nucleus of an atom are protons and electrons.

5 0

3 years ago

A student dissolves of 15 g aniline in of a solvent with a density of . The student notices that the volume of the solvent does

VikaD [51]

The given question is incomplete. The complete question is ;

A student dissolves of 15 g aniline in 200 ml of a solvent with a density of 1.05 g/ml. The student notices that the volume of the solvent does not change when the aniline dissolves in it. Calculate the molarity and molality of the student's solution. Be sure each of your answer entries has the correct number of significant digits.

Answer: The molarity is 0.81 M and molality is 0.82 m

Explanation:

Molarity of a solution is defined as the number of moles of solute dissolved per Liter of the solution.

$Molarity=\frac{n\times 1000}{V_s}$

where,

n= moles of solute

$V_s$ = volume of solution in ml = 200 ml

${\text {moles of solute}=\frac{\text {given mass}}{\text {molar mass}}=\frac{15g}{93g/mol}=0.16mol$

Now put all the given values in the formula of molarity, we get

$Molarity=\frac{0.16\times 1000}{200}=0.81M$

Thus molarity is 0.81 M

Molality of a solution is defined as the number of moles of solute dissolved per kg of the solvent.

$Molarity=\frac{n\times 1000}{W_s}$

where,

n = moles of solute

$W_s$ = weight of solvent in g

${\text {moles of solute}=\frac{\text {given mass}}{\text {molar mass}}=\frac{15g}{93g/mol}=0.16mol$

Mass of solution = $Density\times Volume=1.05g/ml\times 200ml=210g$

mass of solvent = mass of solution - mass of solute = (210 - 15) g = 195 g

Now put all the given values in the formula of molality, we get

$Molality=\frac{0.16\times 1000}{195g}=0.82mole/kg$

Therefore, the molality of solution is 0.82m

3 0

3 years ago

n order to balance the following reaction S n+Cl 2→ S nCl 4, which coefficient should be inserted in front of chlorine?

victus00 [196]

Answer:

The coefficient that should be inserted in front of chlorine is 2

Explanation:

Sn + 2Cl₂ → SnCl₄

As we have 4 atoms of chlorine in product side, we need 4 Cl in reactant side.

Chlorine is a diatomic atom, so if we have 2 mol of it, we are having 4 atoms of Cl.

The law of conservation of mass must be respected in every chemical equation

4 0

3 years ago

For the reaction co(g)+h2o(g)⇌h2(g)+co2(g), k= 4.24 at 800 k what can be said about this reaction at this temperature?

Amanda [17]

The question has missing information.

The options are given below.

a.The equilibrium lies far to the right

b. The reaction will proceed very slowly

c. The reaction contains significant amounts of products and reactants at equilibrium.

d. The equilibrium lies far to the left

Answer : The correct answer is option c: The reaction contains significant amounts of products and reactants at equilibrium.

Explanation :

Option a is not correct because for equilibrium to lie far to the right, we need a large value of keq ( Keq >>> 1 ), but the keq value is small.

option b is also not correct because in order to predict the speed of the reaction, we need more information. The speed of the reaction cannot be predicted using Keq value.

Option d is not correct because for Keq to lie far to the left, it has to be very very small. ( Keq <<< 1)

The value of equilibrium constant is given as 4.24. This value is very near to 1.

Equilibrium constant for this reaction is calculated as

$Keq = \frac{[H_{2}] [CO_{2}]}{[H_{2}O][CO]}$

When Keq = 1, $[H_{2}] [CO_{2} ] = [CO] [H_{2}O]$

That means concentrations of products and reactants are equal.

Since the keq value for our reaction is very close to 1, we can say that , there are significant amounts of reactants and products at equilibrium.

Therefore option C is the correct option.

8 0

4 years ago

Read 2 more answers