In order to <span>complete and balance the following reactions, you should add a Fe into it. So it will look like uo2+ +cr o^2- 7 ـــــــــــــــــــــ uo2+ +cr3+Fe. The answer to the following given statement or missing answer is Fe. </span>
Answer is: chemical.
If the arrangement of particles is changed, that is chemical change or chemical reaction (new substance is formed).
In physical change, the bonds between oxygen and hydrogen can not be separated.
For example, balanced chemical reaction: 2Mg(s) + O₂(g) → 2MgO(s).
Chemical changes (chemical synthesis) is when a substance combines with another (in this example magnesium and oxygen) to form a new substance.
Answer: Single replacement Reaction
Explanation:
A replacement reaction is a chemical reaction in which an element replaces another element in a compound especially when it is more reactive than the former. There are two types of replacement reaction, the single and double replacement reaction.
In the former, one element which is usually more reactive than the other replaces it . For example in the single replacement, a more reactive metal replaces a less reactive metal and also a more reactive non metal can replace a less reactive non metal.
A + BC → B + AC
looking at the equation aove, you can see that B replaces A
Also In double replacement, the elements in the both reacting compounds are replaced or exchanged to form new compounds as can be illustrated in the equation
AB + CD —— AC + BD
In the case of Coach Kwan, she follows the Single replacement model as she substitutes a less active and tired player with an active one.
Answer: A chemical reaction that releases heat into its environment
Explanation:
the exothermic process is a process or reaction that releases energy, (usually in the form of heat but also in light, electricity, or sound) into its environment
ex:
think of ice freezing, to change from a liquid to a solid it must release heat to lower it’s temperature to reach its freezing point
Answer:
Barium.
Explanation:
Each chemical element is characterized by the number of protons in its nucleus, which is called the atomic number Z. But in the nucleus of each element it is also possible to find neutrons, whose number can vary. The atomic mass (A) is obtained by adding the number of protons and neutrons in a given nucleus.
The same chemical element can be made up of different atoms, that is, their atomic numbers are the same, but the number of neutrons is different. These atoms are called isotopes of the element. Isotopes means "same place", that is, since all the isotopes of an element have the same atomic number, they occupy the same place in the Periodic Table. So if a neutron is added to an atom, it becomes an isotope of that chemical element.
The isotopes of an element have the same chemical properties, but differ somewhat in their physical properties.
Barium has an atomic number of 56 (number of protons). Also, the mass number of this barium isotope is 130 (56 protons + 76 neutrons). Finally, since it has 54 electrons, two negatively charged electrons less than the number of positively charged protons, this isotope is a cation with oxidation number +2.
