1.386 g of Mg ribbon combusts to form 2.309 g of oxide product. The mass percent of oxygen in the oxide is 40.0 %.
Let's consider the reaction for the combustion of Mg.
Mg + 1/2 O₂ ⇒ MgO
1.386 g of Mg combusts to form 2.309 g of MgO. We want to determine the mass of oxygen in MgO. According to Lavoisier's law of conservation of mass, matter is not created nor destroyed over the course of a chemical reaction. Then, the mass of Mg in the reactants is equal to the mass of Mg in MgO. The mass of the magnesium oxide is the sum of the masses of magnesium and oxygen. The <u>mass of oxygen in the oxide</u> is:
We can calculate the mass percent of O in MgO using the following expression.
You can learn more about mass percent here: brainly.com/question/14990953
The simple trick which one can consider in such problem where it is asked for positron emission is :
<span>When the atomic number goes DOWN by one and mass number remains unchanged, then a positron is emitted.
</span>
<span>a. </span>
<span>
Here the atomic number decreases by one.
Similarly, options b and d are eliminated.
Option c is also not the answer.
For c, Count the atomic number on left side and compare it with right side. You will see it is 9 on left and 8 on right. Atomic no. did go down by 1. But the atomic mass is changed as well.
</span>
Answer: Option 1 and 11
1. Organic solvents are often flammable.
II. Organic solvents are often toxic.
Explanation:
Organic solvents are often flammable and Organic solvents are often toxic are the reasons why organic chemistry is a primary target of green chemistry because green chemistry is the use of principles or approach to remove hazardous or toxic substances from chemical.profuctd or processes to make them fit or safe for use and the solvents of organic chemist are toxic, therefore green chemistry remove the toxic substances.
Answer: Magnets have a force which is known as no contact force. This force tries to attract the metallic objects near it, which makes it move.
Explanation:
