A chemical substance has the characteristics that it cannot be separated by physical methods. Seawater and milk can be separated by sedimentation, and air has different components depending on other aspects (such as elevation). Only ammonia is a substance. (thus it can have a formula: NH<span>3)</span>
Density is a property of a material which describes the mass of a material per unit volume. Density is said to be slightly dependent on temperature. We look at the density of water at different temperatures:
<span>
100 </span>°C: 958.4 kg/m^360 °C: 983.2 kg/m^320 <span>°C</span>: 998.2 kg/m^3
Therefore, warm water has a lower density than water in colder temperature.
Answer: Potassium Chloride
Explanation:
Answer:
M Na2SO4 sln = 0.8448 M
Explanation:
∴ mass Na2SO4 = 3.00 g
∴ volume soln = 25 mL = 0.025 L
∴ molar mass Na2SO4 = 142.04 g/mol
⇒ mol Na2SO4 = (3.00 g)*(mol/142.04 g) = 0.02112 mol
⇒ M Na2SO4 sln = (0.02112 mol/0.025 L ) = 0.8448 M
Answer:
The central atom has 3 electron domains.
Explanation:
According to the Valence Shell electron pair repulsion theory (VSEPR) put forward by Gillespie and Nyholm in 1957, the shape of a molecule is determined by repulsion between all the electron pairs (electron domains) present in the valence shell.
The electron pairs or electron domains are known to position themselves as far apart in space as possible in order to minimize repulsions.
Hence, when the central atom of a molecule contains three electron domains, they are positioned at an angle of 120° from each other to minimize repulsions. Hence the answer.
