Answer:
The conversion of liquid water into gaseous water is a chemical change
Explanation:
A chemical change occurs when there is a chemical reaction, so there'll be changed in the compounds, such as forming new ones, forming its elements, or elements forming compounds.
A physical change occurs when there is a change in the state of aggregation of the compound, it means that it changes its physical state. Solid for liquid, liquid for solid, liquid for gas, gas for liquid, solid for gas, and gas for solid are the physical changes.
So the evaporation of water, or its conversion in gaseous water, is a physical change, not a chemical change.
i believe its true bc ik for sure air is a homogenous mixture
<span>A chemist adds 155.0ml of a 4.10 X 10^-5 mmol/L of a zinc oxalate (ZnC2O4)solution to a reaction flask. Calculate the mass in micrograms of zinc oxalate the chemist has added to the flask.
1mmol = 10^-3 mol
Therefore 4.10*10^-5mmol = 4.10*10^-8mol
molar mass ZnC2O4 = 65.39+(2*12.011)+(4*15.99) = 153.372g/mol
You have 4.10*10^-8 mol/litre =153.372 * 4.10*10^-8 = 6.29*10^-6 grams / litre (* see below)
But you have 155ml. Mass of ZnC2O4 = 155/1000*6.29*10^-6 g
Mass is = 9.75*10^-7 grams
1µg = 10^-6 g
You then have 9.75*10^-7/10^-6 = 0.975µg ZnC2O4
(*see below) at this point you could have said:
1µg = 10^-6 g therefore you have a solution of 6.29µg per litre,
155ml = 6.29*155/1000 = 0.975µg ZnC2O4</span>
