Answer:
1. 
2. 
Explanation:
An ion is formed when an atom that is said to be neutral gains or losses electrons.
It is thought that a negative ion (anion) is produced as it gains electrons and a positive ion (cation) is formed when it loses an electron.
Atomic number is the total number of protons and electrons in a neutral atom.
From the information
Protons = 14
electron = 18
Net Charge = no of proton - no of electron
= 14 - 18 = -4
Mass number = 14 + 15 = 29
Thus, the chemical symbol =
For ion with 27 proton, 32 neutrons and 25 electrons
Net charge = 27 - 25 = +2
Mass number = 27 + 32 = 59
Thus, the chemical symbol =
Answer:
The half life is 
Explanation:
The half life of a first order reaction is mathematically represented as
Substituting 
for the rate constant
Answer:
44 grams/mole
Explanation:
<u>If 1 mol of XO₂ contains the same number of atoms as 60 g of XO3, what is the molar mass of XO₂?</u>
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60 grams of XO3 is one mole XO3, since it has the same number of atoms as 1 mole of XO2.
Let c be the molar mass of X. The molar mass of XO3 is comprised of:
X: c
3O: 3 x 16 = 48
Total molar mass of XO3 is = <u>48 + c</u>
We know that the molar mass of XO3 = 60 g/mole, so:
48 + c = 60 g/mole
c = 12 g/mole
The molar mass of XO2 would be:
1 X = 12
2 O = 32
Molar mass = 44 grams/mole, same as carbon dioxide. Carbon's molar mass is 12 grams.
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Answer:
Endangered. The meaning of endangered is when a species declines in number- this might be because they are being eaten by another animal which has a higher popupayion, or perhaps because they are being hunted by humans for their meat or fur. Neither reason might be that their food or habitat has been destroyed b humans to create land for farming or housing. one example of name endangered species is Polar Bears: they like in the Antarctic where there is no land, simply ice. Due to humans causing climate change, the world is warming up and the ice is melting. This means polar bears are dying out because it would be too tiring to swim to find ice. For the same reason, other animals are dying in the Antarctic meaning that Poplar Bears have less to eat (being at the top of the food chain -no animal eats polar bears).
Answer:
D
Explanation:
It is higher in the air, so it will fall faster then the other apples.
