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Mg grams -> (use Mg's molar mass) -> Mg moles -> (use ratio of moles - use balanced equation) -> MgO moles -> (use MgO's molar mass) -> grams MgO

set up the equation:

Mg + O2 --> MgO

(we know the product is MgO and not MgO2 because magnesium has a charge of 2+ while oxygen has a charge or 2-)

balance the equation:

2Mg + O2 --> 2MgO

Molar mass of Mg: 24.31 g/mol

Molar mass of MgO: 44.30 g/mol (add the molar mass of Magnesium - 24.31g/mol and the molar mass of Oxygen - 15.99g/mol together)

(use Periodic Table to find these)

7.0 grams of Mg

To find the moles of Magnesium you use the molar mass of Mg.

(7.0 g Mg)*(1 mol Mg / 24.31 g Mg) =0.2879 moles Mg

notice how the grams cancel to leave you with moles - remember dividing by a fraction is the same as multiplying by the reciprocal

Now use the balanced equation's coefficients and the moles of Mg to determine the number of moles of MgO present.

2Mg + O2 --> 2MgO

2 moles Mg : 2 moles MgO -> divide both sides by 2 and it obviously becomes a 'one to one' ratio. This means that the number of moles of Mg is equal to the number of moles of MgO. This means that there are 0.2879 moles of MgO.

Now that we know MgO's molar mass and the number of moles of MgO we have, the grams of MgO produced can be determined.

(0.2879 moles MgO)*(44.30 g MgO / 1 mol MgO) = 12.75 grams MgO

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15y ago
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8mo ago

When you burn 4 grams of magnesium, it combines with oxygen to form magnesium oxide. The molar mass of magnesium is 24.31 g/mol, and oxygen is 16.00 g/mol. By using stoichiometry, we can calculate that the mass of magnesium oxide formed will be 8 grams.

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12y ago

Let's start by writing a chemical equation for the reaction.

Mg (s) + O2 (g) ----> MgO (s)

According to the Law of Conservation of Mass, the amount of moles of each reagent before the reaction must equal the number of moles of each original reagent after the reaction. We must balance the equation:

2Mg (s) + O2 (g) ----> 2MgO (s)

We assume that the reaction occurs in excess oxygen and that all 8.0 grams of magnesium is completely burned. We then use stoichiometry to find the amount of MgO formed.

(8.0g Mg)(1 mol Mg / 24.3050g Mg)(2 mol MgO / 2 mol Mg)(40.3044g MgO / 1 mol MgO) = 13.3g MgO is formed

So overall 13.3g MgO is formed

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7y ago

You might want to know why 1.99 g is the answer, or how to calculate it. This answer is arrived at as follows:2Mg + O2 ==> 2MgO ... balanced chemical equation

1.2 g Mg x 1 mole/24.3 g = 0.049 moles Mg

Since 2 moles Mg produces 2 moles MgO, this is a 1:1 mole ratio, thus...

0.049 moles Mg will produce 0.049 moles MgO

0.049 moles MgO x 40.3 g/mole = 1.98 grams = 2.0 grams (to 2 significant figures)

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15y ago

Balanced equation.

2Mg + O2 >> 2MgO

8 grams MgO ( 1mol MgO/40.31g )(1 mol O/2 mol MgO )(16g O/1mol O) = 1.59 grams

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14y ago

2Mg + O2 ----->2MgO

48g Mg gives 80 grams of MgO

4g Mg of gives 80/48 x 4= 80/12=20/3= 6.67g of MgO

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7y ago

The magnesium oxide (MgO) obtained theoretically is 1,99 g.

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Q: What is the mass of magnesium oxide when you burn 4 grams of magnesium?
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Does the coating on a magnesium strip change the mass of magnesium oxide?

Yes, the coating on a magnesium strip can affect the mass of magnesium oxide because the coating can add additional mass to the strip. When the magnesium reacts with oxygen to form magnesium oxide, the mass of the coating is also included in the total mass of the resulting compound.


When 24g of magnesium metal is heated in air 40g of magnesium oxide is produced. What mass of magnesium would be needed in order to produce 10g of magnesium oxide?

6g


What happens to the MASS when MAGNESIUM is burnt inside a CONTAINER?

When magnesium is burnt inside a container, it undergoes a chemical reaction with oxygen to form magnesium oxide. The total mass of the system will remain the same before and after the reaction, according to the law of conservation of mass. However, the mass of the magnesium itself will decrease as it transforms into magnesium oxide.


How many grams of oxygen gas is consumed in burning magnesium?

A balanced equation for the reaction is 3 Mg + 3/2 O2 = 3 MgO. the atomic mass of mass of magnesium is about 24.3 and that of oxygen is about 16.0; therefore the mass of magnesium oxide produced is 3 (24.3 + 16.0) = 120.9 grams. (If the specification of "3 moles" of magnesium is considered to have only one significant digit, this answer should be written instead as 1 X 102 grams.)


What is the charge of the magnesium in magnesium oxide?

The molar mass of Magnesium Oxide (MgO) is 40.3044 grams per mole. This means in chemistry terms that there is 1 gram per 6.02 x 1023 molecules of Magnesium Oxide (the ratio for grams to molecules would be 1:6.02 x 1023)

Related questions

In the reaction between magnesium and oxygen the mass of magnesium and oxygen was 2.5 grams how much magnesium oxide was formed?

The molar mass of magnesium is 24.3 g/mol and oxygen is 16 g/mol. The balanced equation is 2Mg + O2 -> 2MgO. Since magnesium and oxygen react in a 1:1 ratio, all magnesium reacted to form magnesium oxide. Therefore, 2.5 grams of magnesium oxide was formed.


How many grams of magnesium oxide and oxygen react to form 20.0 grams of magnesium oxide?

To determine the amount of oxygen, we first find the amount of magnesium by subtracting the given 20.0 grams of magnesium oxide from the total. Given that the molar mass of magnesium oxide is 40.3 g/mol and that of magnesium is 24.3 g/mol, we calculate the amount of oxygen by adjusting accordingly. This process gives us the weight ratio of magnesium oxide to oxygen.


Does the coating on a magnesium strip change the mass of magnesium oxide?

Yes, the coating on a magnesium strip can affect the mass of magnesium oxide because the coating can add additional mass to the strip. When the magnesium reacts with oxygen to form magnesium oxide, the mass of the coating is also included in the total mass of the resulting compound.


What is the mass of 24.6 formula units of magnesium oxide?

To find the mass of 24.6 formula units of magnesium oxide, you first need to determine the molar mass of magnesium oxide (MgO), which is 40.3 g/mol. Then, multiply the molar mass by 24.6 to find the mass: 40.3 g/mol x 24.6 = approximately 992 grams.


Why when magnesium ribbon is burnt the ash is heavier?

When Magnesium burns, it is actually combining with oxygen in the air to form a new compound, magnesium oxide. If we were to carefully weigh a piece of magnesium before and after burning it, you would see that its weight increased by about one third. For example, if you start with 100 grams of magnesium, after the burn you would end up with about 130 grams of magnesium oxide. The fact that the magnesium oxide you create by burning is powdery, means that it takes up more space (size or volume) than the solid magnesium did.


What is the ratio of magnesium oxide mass to the magnesium mass?

.659


Why does magnesium get heavier when its burned?

When magnesium is burned, it combines with oxygen from the air to form magnesium oxide. This reaction increases the overall weight of the magnesium because the newly formed magnesium oxide has a greater mass than the original magnesium metal due to the added oxygen atoms.


Magnesium oxide decomposes into magnesium and oxygen If 4.03 of magnesium oxide decomposes to form 2.43 of magnesium what mass of oxygen gas is also released in the reaction?

To find the mass of oxygen gas released, you need to calculate the mass of magnesium oxide that contributed to the formation of 2.43g of magnesium. Molar mass of MgO = 40.3g/mol Molar mass of Mg = 24.3g/mol Calculate the moles of Mg formed and use stoichiometry to find the moles of oxygen reacted. Finally, convert the moles of O2 to grams to find the mass of oxygen gas released.


Why does the mass of magnesium increase when you burn it in air?

The mass of magnesium increases when burned in air due to the reaction with oxygen in the air. The magnesium atoms combine with oxygen atoms to form magnesium oxide, which has a greater mass than the original magnesium atoms. This increase in mass is due to the addition of oxygen atoms from the air to form a new compound.


What happens to the mass when magnesium is heated in air?

When magnesium is heated in air, it reacts with oxygen to form magnesium oxide. The total mass of the system, which includes the magnesium and the oxygen it reacts with, remains the same according to the Law of Conservation of Mass.


Why is a mass bigger if magnesium is burned in oxygen?

When magnesium is burned in oxygen, it undergoes a chemical reaction called combustion. During this reaction, magnesium atoms combine with oxygen atoms to form magnesium oxide. The increased mass observed after burning magnesium is due to the formation of magnesium oxide, which adds the combined mass of magnesium and oxygen atoms to the initial mass of the magnesium.


When 24g of magnesium metal is heated in air 40g of magnesium oxide is produced. What mass of magnesium would be needed in order to produce 10g of magnesium oxide?

6g