Scientific investigation is the process in which scientist solve the problems by using different systematic approach. It can be initiated in different ways.
Experimental Scientific investigation: The investigation in which scientist answer the question on the basis of experimental results. Experimental investigation contains both dependent and independent variables, and only one variable is tested at a time is possible. This process makes uses of collecting observation and identifying the process in physical word.
Noting the colour of a solution when heated is the experimental scientific investigation
Therefore, other given options are part of scientific observation whereas Noting the colour of a solution when heated explains the experimental scientific investigation.
Answer:
D
Explanation:
the Same number of proton
1. (b) I hope this helps!
Answer:
15.5g
Explanation:
"The total mass of both chemicals and the containers they are in is 15.5 g." After a chemical reaction, by conservation of mass, the total mass of the products and the two containers after reaction is the same at 15.5g.
Answer:
A. 8.8 g.
B. 5.3 g.
C. 449 g.
Explanation:
A. Determination of the mass of CO2.
Mole of CO2 = 0.2 mole
Molar mass of CO2 = 12 + (2×16)
= 12 + 32
= 44 g/mol
Mass of CO2 =?
Mole = mass /Molar mass
0.2 = mass of CO2 /44
Cross multiply
Mass of CO2 = 0.2 × 44
Mass of CO2 = 8.8 g
B. Determination of the mass of Na2CO3.
Mole of Na2CO3 = 0.05 mole
Molar mass of Na2CO3 = (2×23) + 12 + (3×16)
= 46 + 12 + 48
= 106 g/mol
Mass of Na2CO3 =?
Mole = mass /Molar mass
0.05 = mass of Na2CO3 /106
Cross multiply
Mass of Na2CO3 = 0.05 × 106
Mass of Na2CO3 = 5.3 g
C. Determination of the mass of Fe(OH)2.
Mole of Fe(OH)2 = 5 moles
Molar mass of Fe(OH)2 = 55.8 + 2(16 + 1)
= 55.8 + 2(17)
= 55.8 + 34
= 89.8 g/mol
Mass of Fe(OH)2 =?
Mole = mass /Molar mass
5 = mass of Fe(OH)2/89.8
Cross multiply
Mass of Fe(OH)2 = 5 × 89.9
Mass of Fe(OH)2 = 449 g.
