In order to determine the density of an item, we will need to determine its mass and volume. The standard unit for measuring mass in a lab is the gram. Think about liquids- what units do you typically report the volume of a liquid in? What about for a sugar cube, what volume is the most appropriate?
A regular object like a sugar cube can be measured with a ruler so we might report the volume in centimeters cubed (cm3). An irregular object like the plate pictured below can be measured by using a technique called volume by displacement. A liquid (typically water) is placed in a graduated cylinder and the volume of a liquid is measured. Then the irregular object is placed in the liquid and the volume is measured again. The change in volume is the irregular object’s volume. This measurement is often made using a graduated cylinder and recording a volume in Liters or milliliters (mL).
Figure 1. (a) Regular object of metal blocks with the same width, length, and height. (B) An irregular
Science does not have anything to say about right and wrong the meaning of life or the extensive or the subjective
Answer:
a) Neutralisation
b) Combustion
c) Synthesis
d) Decomposition
e) Neutralisation
f) Double Displacement Reaction
h) Single Displacement Reaction
i) Double Displacement Reaction
j) Combustion
Explanation:
Synthesis is a reaction where various compounds/ elements react to form a totally new compound.
Decomposition is a reaction where a single compound breaks down into several components due to excessive heating or energy applied.
Single Displacement Reaction is a type of chemical reaction where an element reacts with a compound and takes the place of another element in that compound.
Double Displacement Reaction is a type of chemical reaction where two compounds react, and the positive ions (cation) and the negative ions (anion) of the two reactants switch places, forming two new compounds or products.
Combustion is a reaction where a compound/ element oxidises in the presence of Oxygen.
Neutralisation reaction is a reaction where an acid reacts with a base to form a salt.
Answer:
2.52 g NaCl
Explanation:
(Step 1)
To find the mass, you first need to find the moles NaCl. This value can be found using the molarity ratio:
Molarity = moles / volume (L)
After you convert mL to L, you can plug the given values into the equation and simplify to find moles.
136.9 mL / 1,000 = 0.1369 L
Molarity = moles / volume
0.315 M = moles / 0.1369 L
0.0431 = moles
(Step 2)
Now, you can use the molar mass to convert moles to grams.
Molar Mass (NaCl): 22.990 g/mol + 35.453 g/mol
Molar Mass (NaCl): 58.443 g/mol
0.0431 moles NaCl 58.443 g
------------------------------ x ------------------- = 2.52 g NaCl
1 mole
