Answer:
A. your observations in writing
Explanation:
Descriptive investigation is one of the mode of inquiries in science. It is devoid of the usual collection of data in the field or setting up laboratory experiments to compared variables.
- In descriptive investigation, observations are usually done in writing.
- They are usually common in Astrology.
- Such investigation involves a question without a hypothesis ensuing.
- Tests are usually not carried out in descriptive investigation.
Answer:
Question 8, I think is C describe CR. Question 7 is Chemical reactions produce new substances
Explanation:
Find the molar mass of CH3 and divide that by 45.0. That should give a whole number and then mult that whole number by CH3 to find molecular formula to get like ( incorrect ex: C2H6) which is mult by 2
Answer:
Heat required to melt 26.0 g of ice at its melting point is 8.66 kJ.
Explanation:
Number of moles of water in 26 g of water: 26× 
moles
=1.44 moles
The enthalpy change for melting ice is called the entlaphy of fusion. Its value is 6.02 kj/mol.
we have relation as:
q = n × ΔH
where:
q = heat
n = moles
Δ
H = enthalpy
So calculating we get,
q= 1.44*6.02 kJ
q= 8.66 kJ
We require 8.66 kJ of energy to melt 26g of ice.
Mario places 10 mL of water in a test tube and heats the liquid over a Bunsen burner for 2 minutes. After removing the test tube from the Bunsen burner, there are 6 mL of water left in the test tube. This experiment is a good example of a <span>physical change involving phase changes. </span>
