Answer:
1. observations
2. hypothesis
3. experimentation
Explanation:
Observations are made, Hypothesies are formed from observations, and experimnets help alter and comfirm hypothesis.
Answer : Option A) Ethanoic Acid
Explanation : Ethanoic acid has the lowest vapor pressure i.e 0.08 atm at the temperature of 50°C compared to the other given options.
The vapour pressure of propanone at 50°C is 0.84 atm
Ethanol has vapour pressure as 0.30 atm at 50°C
water has vapour pressure of 0.12 atm at 50°C.
<span>There are a number of ways
to express concentration of a solution. This includes molality. Molality is
expressed as the number of moles of solute per mass of the solvent. We calculate as follows:
0.200 mol I2 / kg CCl4 ( .750 kg CCl4 ) ( 253.809 g I2 / mol I2) = 38.07 g I2 needed
Hope this helps.
</span>
I will solve this question assuming the reaction equation look like this:
<span>MnO2 + 4 HCl ---> MnCl2 + Cl2 + 2 H2O.
</span>
For every one molecule of MnO2 used, there will be one molecule of Cl2 formed. If the molecular mass of MnO2 is 87g/mol and molecular mass of Cl2 is <span> 73.0 g/mol, the mass of MnO2 needed would be:
Cl mass/Cl molecular mass * MnO2 molecular mass=
25g/ (73g/mol) * (87g/mol) * 1/1= 29.8 grams</span>
The change is thermal energy to chemical energy. Sugar contains a lot of chemical potential energy which is why living things use it as a source of energy. The process of photo synthesis takes light from the sun to convert carbon dioxide and water into sugar and oxygen. That process is basically turning the thermal energy from the light into chemical energy in the sugar.
I hope this helps. Let me know if anything is unclear.