Answer:
2Mg + O₂ → 2MgO
Explanation:
Chemical equation:
Mg + O₂ → MgO
Balanced chemical equation:
2Mg + O₂ → 2MgO
The balanced equation s given above and it completely follow the law of conservation of mass.
Law of conservation of mass:
According to the law of conservation mass, mass can neither be created nor destroyed in a chemical equation.
This law was given by french chemist Antoine Lavoisier in 1789. According to this law mass of reactant and mass of product must be equal, because masses are not created or destroyed in a chemical reaction.
Steps to balanced the equation:
Step 1:
Mg + O₂ → MgO
Mg = 1 Mg = 1
O = 2 O = 1
Step 2:
2Mg + O₂ → MgO
Mg = 2 Mg = 1
O = 2 O = 1
Step 3:
2Mg + O₂ → 2MgO
Mg = 2 Mg = 2
O = 2 O = 2
The Great Oxidation Event (GOE), sometimes also called the Great Oxygenation Event, Oxygen Catastrophe, Oxygen Crisis, Oxygen Holocaust,[2] or Oxygen Revolution, was a time period when the Earth's atmosphere and the shallow ocean first experienced a rise in oxygen, approximately 2.4 billion years ago (2.4 Ga) to 2.1–2.0 Ga during the Paleoproterozoic era.[3] Geological, isotopic, and chemical evidence suggests that biologically produced molecular oxygen (dioxygen, O2) started to accumulate in Earth's atmosphere and changed Earth's atmosphere from a weakly reducing atmosphere to an oxidizing atmosphere,[4] causing many existing species on Earth to die out.[5] The cyanobacteria producing the oxygen caused the event which enabled the subsequent development of multicellular forms.
Answer:
Explanation:
1. New substances such as carbondioxide and water is formed.
2. There is evolution of gas bubbles. Gases are released.
3. There is either the absorption of energy or release of energy in form of light and energy.
4. The reaction is irreversible i.e it cannot be reversed, it is permanent once the reaction take place.
5. There is a change in both odor and smell.
A chemical change is a change where new substances are formed due to changes in the properties.
Blood.
<span>Blood is heterogeneous because it has corpuscles (blood cells and platelets) physically suspended in blood plasma. Blood plasma and the corpuscles have different properties and can be separated by methods such as centrifugation. Also, blood is considered a colloid suspension because it has the properties of both a colloid and a suspension. This is because the blood plasma acts as a colloid. More so, if blood was left to settle,then the blood cells would collect at the bottom hence taking the characteristic of a suspension. </span>
<span>Salad dressing.</span>
<span>Depending on the type of salad, it can either be a heterogeneous or homogeneous mixture. If the salad dressing is only of vinegar or any other oil, then it is a homogenous mixture. However, if it involves a mixture of vinegar and other oils, pepper, herbs, and etcetera, then it is a heterogeneous mixture</span>
