It would be 1 or 2 because if the number is higher than 5 you need to round up , if its lower than 5 you need to round down.
Answer : The correct expression will be:
Explanation :
The chemical reactions are :
(1) 
(2) 
The final chemical reaction is :
Now we have to calculate the value of 
for the final reaction.
Now equation 1 is multiply by 2 and then add both the reaction we get the value of 'K'.
If the equation is multiplied by a factor of '2', the equilibrium constant will be the square of the equilibrium constant of initial reaction.
If the two equations are added then equilibrium constant will be multiplied.
Thus, the value of 'K' will be:
Answer:
A) yes
B) The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
Explanation:
A) I think the the Bureau of Mint changed the way it made pennies because from the experiment and observation carried out on 15 different pennies it can be seen that they had different weights and this difference is associated with the period/time of production of the different pennies,
B ) The average mass of any object should be expressed in the si unit of mass and not having ($) sign attached to the value instead it should be expressed in grams or kilograms (s.i unit of mass )
The average mass of 12 pennies should be expressed as
( 3.131 + 3.129 + -------- X12 ) g / 12
where X12 = is the mass of the 12th penny
Answer:
The equipments you should have ready to start the crucible experiment includes: safety goggles, crucible with lid, crucible tong, ring support with clay triangle, Bunsen burner and heat resistant tile.
Explanation:
Crucible is an equipment in the laboratory which is suitable for heating a sample to extreme heat over a flame, Modern laboratory crucible are made up of graphite- based composite materials for achievement of higher performance. Because extreme heat is involved, you should locate the correct labware for the experiment, including the equipment to safely handle and support the crucible. These equipments includes:
--> Safety goggles: Because you will work with chemical it is advisable to use a safety goggles which protects the eyes from dangerous floating chemical aerosol.
--> crucible with lid: This is the main apparatus with the lid (cover) which is used to cover the crucible to prevent spilling of the boiling chemical.
--> Crucible tong: These are scissors like tools used to grasp hot crucible.
--> Ring support with clay triangle: the clay triangle is used to hold crucible when they are being heated. They usually sit on a ring stand.
--> Bunsen burner: Produces a single open gas flame which can be used for heating.
With the safety equipments listed above, you can carry out experiment using the crucible. These equipments helps minimise laboratory hazard that may occur should Incase it's not available.
Answer:
178.35g
Explanation:
Molarity of a solution can be calculated using the formula:
Molarity = number of moles ÷ volume
Based on the information provided in this question, molarity (M) of the solution = 1.50 M, volume = 725 mL = 725/1000 = 0.725L, n = ?
1.50 = n / 0.725
n = 1.50 × 0.725
n = 1.0875mol
Molar mass of Na3PO4
23(3) + 31 + 16(4)
= 69 + 31 + 64
= 164g/mol
Mole = mass ÷ molar mass
1.0875 = mass/164
mass = 178.35g
