Answer:
Calculated density = 0.8555g/ mL
Probable identity = Toulene
Explanation:
First off, the substance choices are;
isopropyl alcohol (density 0. 785 g/ mL)
toluene ( density 0.866g/ mL)
So upon calculation, if the density of the liquid substance is equal to either of the substances in the choice, it is that substance.
The relationship between density, mass and volume is given as;
Density = Mass / Volume
Mass = 38.5g
Volume = 45ml
Density = 38.5 / 45 = 0.8555g/ mL
Calculated density = 0.8555g/ mL
Among both substances, it is closest to toluene ( density 0.866g/ mL).
Probable identity = Toulene
Answer:
0.027g
Explanation:
From Avogadro's hypothesis, 1mole of any substance contains 6.02x10^23 molecules.
From the above, it means that 1mole of SO3 also contains 6.02x10^23 molecules.
1mole of SO3 = 32 + (16x3) = 32 + 48 = 80g
If 1 mole (80g) of SO3 contains 6.02x10^23 molecules,
Then Xg of SO3 will contain 2x10^20 molecules i.e
Xg of SO3 = (80x2x10^20)/6.02x10^23 = 0.027g
Answer:
Rusting is a chemical change while breaking down of ricks may just be due to mechanical weathering of rocks
Explanation:
Rusting is a chemical reaction. Rust refers to hydrated iron III oxide. This substance is soft and flakes easily hence making the iron soft and brittle. The entire process of rusting is an electrochemical reaction set up with water as the electrolyte.
Mechanical weathering is the process of breaking big rocks into smaller pieces. The process usually occurs near the surface of the earth. The cool nights and hot days always cause rocks to expand and contract. This movement can cause rocks to crack and break apart. The entire process is a physical process.
Hence rusting makes iron brittle and flake by a chemical process while mechanical weathering break rocks in pieces by a physical process.
Answer:
Amount of mercury is 1.0*10⁻⁵ g
Explanation:
<u>Given:</u>
Mercury content of stream = 0.68 ppb
volume of water = 15.0 L
Density of water = 0.998 g/L
<u>To determine:</u>
Amount of mercury in 15.0 L of water
<u>Calculation:</u>
where 1 μg (micro gram) = 10⁻⁶ g
0.68 ppm implies that there is 0.68 *10⁻⁶ g mercury per Liter of water
Therefore, the amount of mercury in 15.0 L water would be:
