All categories

2 years ago

What happens when a piece of Mg ribbon is burnt? Name the

Chemistry

1 answer:

algol132 years ago

7 0

Answer:

When a Magnesium Ribbon is burnt, a powdery substance called magnesium oxide is formed.

Explanation:

There has obviously been a chemical change because several chemical properties of the magnesium have been modified: the color, the texture and the mass.

The increase in mass is due to the fact that oxygen from the air has combined with the magnesium to make magnesium oxide, MgO.

The chemical equation, Mg + O2 MgO shows this reaction but it needs to be balanced to make 2Mg + O2 2MgO.

Using stoichiometry, we can convert this eqation into an equation with moles:

2 mol Mg + 1 mol O2 2 mol MgO.

Next, we convert to grams using atomic masses obtained from the periodic table:

48g Mg + 32g O2 80g MgO

Lastly, we determine the same thing in the proportions we used. In other words, we used only 0.15g of Mg (not 48g) so everything needs to be divided by 320. So 80 / 320 = 0.25 g. If we burn 0.15 g of Mg, we obtain 0.25 g of MgO.

Hope this helps!!!

This is my first answer.

You might be interested in

Identify this reaction

Natasha2012 [34]

Answer:

d a a

Explanation:

brainliest plz

4 0

2 years ago

An unsaturated solution is formed when 80 grams of a salt is dissolved in 100 grams of water at 40. This salt could be ?

LekaFEV [45]

A simple way to go about this is that we look at the solubility curve, on the x axis we first look at the temperature and then the corresponding value of solute/100g H2O on the y axis, from the 4 curves above only NaNO3 has a curve that can accommodate 80g of salt at 40 without being Saturated since at 40 degrees it can accommodate 105g of salt to become completely Saturated.

7 0

3 years ago

Read 2 more answers

How do you write a chemical equation given a word equation ? (Chemistry)

earnstyle [38]

Step one: Identify reactants and products and place them in a word equation.

Step two: Convert the chemical names into chemical formulas. Place them based on the chemical equation and write the state symbols.

Step three: balance the chemical equation.

5 0

3 years ago

Draw the bridged bromonium ion that is formed as an intermediate during the bromination of this alkene. include hydrogen atoms,

gogolik [260]

<h2>Answer</h2>

Bromination:

Any reaction or process in which bromine (and no other elements) are introduced into a molecule.

Bromonium Ion:

The bromonium ion is formed when alkenes react with bromine. When the π cloud of the alkene (acting as a nucleophile) approaches the bromine molecule (acting as an electrophile), the σ-bond electrons of Br2 are pushed away, resulting in the departure of the bromide anion.(2)

Mechanism:

Step 1:

In the first step of the reaction, a bromine molecule approaches the electron-rich alkene carbon–carbon double bond. The bromine atom closer to the bond takes on a partial positive charge as its electrons are repelled by the electrons of the double bond. The atom is electrophilic at this time and is attacked by the pi electrons of the alkene [carbon–carbon double bond]. It forms for an instant a single sigma bond to both of the carbon atoms involved (2). The bonding of bromine is special in this intermediate, due to its relatively large size compared to carbon, the bromide ion is capable of interacting with both carbons which once shared the π-bond, making a three-membered ring. The bromide ion acquires a positive formal charge. At this moment the halogen ion is called a "bromonium ion".

Step 2:

When the first bromine atom attacks the carbon–carbon π-bond, it leaves behind one of its electrons with the other bromine that it was bonded to in Br2. That other atom is now a negative bromide anion and is attracted to the slight positive charge on the carbon atoms. It is blocked from nucleophilic attack on one side of the carbon chain by the first bromine atom and can only attack from the other side. As it attacks and forms a bond with one of the carbons, the bond between the first bromine atom and the other carbon atoms breaks, leaving each carbon atom with a halogen substituent.

In this way the two halogens add in an anti addition fashion, and when the alkene is part of a cycle the dibromide adopts the trans configuration.

6 0

3 years ago

Which of the following represents a physical change?

vivado [14]

A. phase changing. Physical change is any change in matter that involves the substance going from one physical state to another, and phase change is most commonly used to describe transitions between solid, liquid and gaseous states of matter.

8 0

3 years ago