the environment is Healthy
To find this, we will use this formula:
Molar mass of element
------------------------------------ x 100
Molar mass of compound
So, first lets calculate the mass of the compound as a whole. We use the atomic masses on the periodic table to determine this.
Ca: 40.078 g/mol
N2 (there is two nitrogens): 28.014 g/mol
O6 (there are six nitrogens: 3 times 2): 95.994 g/mol
When we add all of those numbers up together, we get 164.086. That is the molar mass for the whole compound. However, we are trying to figure out what percent of the compound oxygen makes up. From the molar mass, we know that 95.994 of the 164.086 is oxygen. Lets plug those numbers into our equation!
95.994
-----------
164.086
When we divide those two numbers, we get .585. When we multiply that by 100, we get 58.5.
So, the percent compostition of oxygen in Ca(NO3)2, or, calcium nitrate, is 58.5%.
<h2>Answer </h2>
Option C - 320J
<u>Explanation </u>
Since ethanol solid at −120 °C and is only cooling down (it won’t change states)
. The amount of Thermodynamic properties values c is given in form of solid, liquid and gas. Amount of energy released is calculated below.
Formula,
= change in temperature x specific heat capacity for solid ethanol x 40
=> 0.5 x 16x 40 = 320J
Therefore, the 320J of heat is released when 40.0g of ethanol cools.
Answer:
Group 1 and 2 elements
Explanation:
Nitrogen, a non-metal will form ionic bonds with most group 1 and group 2 metals on the periodic table.
How does ionic bonds form?
- They are bonds formed between a highly electronegative specie and one with very low electronegativity.
- As such, ionic bonds forms between metals and non-metals
- In this bond type, the metal due to its electropositive nature will transfer electrons to the non-metals for it to gain.
- The non-metals becomes negatively charged as the metal is positively charged.
- The electrostatic attraction between the two specie leads to the formation of ionic bonds.
Most metals in group 1 and 2 fits in this description. Some of them are calcium, magnesium, lithium, Barium e.t.c.
It mostly favors group 2 metals.
