Properties of matter can be broadly classified into two categories:
-Physical properties, these usually involve a change in the state of matter
-Chemical properties. these involve a change in the chemical composition of matter.
Now, physical properties can be further classified as:
Extensive: these depend on the amount of the substance, eg: mass, volume
Intensive: these do not depend on the amount of the substance eg: density, color, melting point, boiling point
A physical property that does not describe a change in state is color. For example: copper sulfate is a compound which is a blue in color. Thus, color provides information which describes the appearance of matter. In contrast, properties like melting or boiling point suggests a change in the state of the substance.
Answer:
=242.47 g of HF
Explanation:
From the equation One mole of SiO₂ (Silicon (IV) Oxide) react with 4 moles of HF (Hydrogen fluoride).
This is because the reaction ratio is 1:4
The number of moles in182 grams of SiO₂ is:
Number of moles= Mass/RMM
RMM of SiO₂ is 60.08 g/mol
No. of moles=182g/60.08g/mol
=3.0293 moles.
The reaction ratio of SiO₂ to HF is 1:4
Thus the number of moles of HF required to react with 3.0293 moles of SiO₂ is:
(4×3.0293)/1= 12.1172 moles
The mass of 12.1172 moles of HF is.
12.1172 moles× RMM of HF
=12.1172 moles×20.01 g/mol
=242.47 g of HF
Answer:
- <u>Option D) 8.5 grams</u>
Explanation:
<u>1) Data:</u>
a) V = 12 liter
b) T = 293 K
c) p = 100 kPa
d) mass = ?
<u>2) Formulae:</u>
a) Ideal gas equation: pV = nRT
b) molar mass = mass in grams / number of moles
<u>3) Solution:</u>
a) <u>Calculate the number of moles of ammonia, n</u>:
- R = universal constant of gases = 8.3145 liter-kPa / mol-K
- n = 100 kPa × 12 liter / (293 K × 8.3145 liter-kPa/mol-K) = 0.493 mol
b) <u>Convert moles to grams:</u>
- Molar mass of NH₃ = 14.007 g/mol + 3×1.008 g/mol = 17.03 g/mol
- mass = 0.493 mol × 17.03 g/mol = 8.4 g
Thus, the answer is the option D. 8.5 grams.
HnX.. H stands for Hydrogen, N stands for the number of Hyrogens and X stands for the monatomic/polyatomic anion that combines w the Hydrogen Atoms.
