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3 years ago

True or false - Evaporating, condensing, melting and freezing are all examples of chemical change.

2 answers:

3 0

False because they can turn back to their original form a chemical change would be like burning paper it can’t be changed back to it’s original offer it’s burnt

S_A_V [24]3 years ago

3 0

Answer:

false

Explanation:

Because these examples are able to turn back into their original form. For example, melted ice can refreeze.

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Write a balanced equation using the correct formulas and include conditions (s, l, g or aq) for each of the following reactions.

Aloiza [94]

Answer:

2Fe(s) + 3Cl2(g) → 2FeCl3(s)

Explanation:

Step 1: Data given

iron = Fe = solid = Fe(s)

chlorine = Cl2 = gas = Cl2(g)

iron(III) chloride = FeCl3 = solid = FeCl3(s)

Step 2: The unbalanced equation

Fe(s) + Cl2(g) → FeCl3(s)

Step 3: Balancing the equation

Fe(s) + Cl2(g) → FeCl3(s)

On the left we have 2x Cl (in Cl2) and on the right side we have 3x Cl (in FeCl3). To balance the amount of Cl we have to multiply Cl2 (on the left) by 3 and FeCl3 by 2.

Fe(s) + 3Cl2(g) → 2FeCl3(s)

On the left side we have 1x Fe and on the right side we have 2x Fe (in 2FeCl3). To balance the amount of Fe, we have to multiply Fe on the left side by 2. Now the equation is balanced.

2Fe(s) + 3Cl2(g) → 2FeCl3(s)

6 0

4 years ago

There are two stereoisomers of 1-tert-butyl-4-chloro-cyclohexane. One of these isomers reacts with sodium ethoxide in an E2 reac

Naily [24]

Answer:

Explanation:

Answer:

cis-isomer reacts faster

Explanation:

The missing diagrams in the question are attached in the first image below and the isomers that react faster are shown in the second image attached.

The cis-isomer quickly follows E2 reaction due to the fact that it is locked in a chair conformation whereby chlorine dominates an axial position, as displayed in drawing C as well as the leaving group Cl which is antiperiplanar to a beta proton.

Due to the bulkiness of tert-butyl, the trans-isomer is Basically trapped in a chair configuration, with chlorine occupying an equatorial position as displayed in drawing A below, thus leaving the group isn't antiperiplanar to a beta proton.

Tert butyl favors an equatorial position due to its bulkiness. This makes the Cl to assume an axial position in an isomer

The difference:

From the second image attached below, in the first diagram(1):

Suppose H is antiperiplanar, C-H bond electrons reach antibonding orbitals of C-Cl, assisting in the breakdown of the C-Cl bond and therefore speeding up the process.

From the second diagram(2) in the second image:

Unless Cl is in the axial position would it have β-hydrogen in the antiperiplanar position. Because tert-butyl prefers equatorial location, the Cl occupies equatorial position in the trans isomer.

As a result, the reaction is slower and there is no β-hydrogen antiperiplanar to Cl.

8 0

3 years ago

Impacts of Erosion and Deposition

VikaD [51]

Answer: Plants

Explanation:

One great and natural option to help to control erosion on slopes is by using plants. The roots of plants act as natural ways to hold in the round and soil and anchor the soil.

7 0

2 years ago

Describe the method to make pure, dry crystals of magnesium sulfate from a metal oxide and dilute acid.

emmasim [6.3K]

Answer:

H2SO4(aq) + MgO(s) → H2O(l) + MgSO4(aq)

Explanation:

We must recall that the oxides of metals are bases. These metal oxides can react with dilute acids to yield salt and water.

Bearing that in mind, we want to obtain magnesium sulfate from a metal oxide and dilute acid.

In this case we need magnesium oxide and dilute sulphuric acid. The reaction occurs as follows;

H2SO4(aq) + MgO(s) → H2O(l) + MgSO4(aq)

6 0

3 years ago

According to Dalton's theory, is it possible to convert atoms of one element into atoms of another? Explain.

Mrrafil [7]

Answer:

No, it's not possible to change the atoms into a different element.

Explanation:

No, because rule four of his theory says that change cannot occur

4 0

3 years ago