Answer:
Q = 2.60 • 
J
Explanation:
Our specific heat capacity equation is:
Q = mC∆T
Q is the energy in joules.
m is the mass of the substance.
∆T is the temperature chance.
Let's plug in what we know.
- We have 76.0 g of octane
- The specific heat capacity of octane is 2.22 J/(g•K)
- The temperature increases from 10.6º to 26.0º (a 15.4º increase)
Q = 76.0(2.22)(15.4)
Multiply.
Q = 2598.288
We want three significant figures.
Q = 2.60 •
or
Q = 2590 J
Hope this helps!
Answer:
A. They must be kept separate from moisture and oxygen
Explanation:
Alkali metals refers to a group of chemical elements in the periodic table. It is the common name given to Group 1 elements (excluding hydrogen). They are generally metallic in nature with physical properties like shining lustre, silvery in appearance etc. Alkali metals include lithium, Pottasium, Sodium, Rubidium etc.
One important chemical property of alkali metals is their high reactivity i.e. they tend to react quickly with other substances. For example, alkali metals react vigorously with water to form hydroxides. They also react with oxygen to form oxides. Due to this highly reactive properties, they are kept or stored away from moisture (water) and oxygen (present in air).
Answer:
30 mL VOLUME OF 3.0 M HCl SHOULD BE USED BY THE STUDENT TO MAKE A 1.80 M IN 50 mL OF HCl.
Explanation:
M1 = 3.00 M
M2 = 1.80 M
V2 = 50 .0 mL = 50 /1000 L = 0.05 L
V1 = unknown
In solving this question, we know that number of moles of a solution is equal to the molar concentration multiplied by the volume. To compare two samples, we equate both number of moles and substitute for the required component.
So we use the equation:
M1 V1 = M2 V2
V1 = M2 V2 / M1
V2 = 1.80 * 0.05 / 3.0
V2 = 0.09 /3.0
V2 = 0.03 L or 30 mL
To prepare the sample of 1.80 M HCl in 50.0 mL from a 3.0 M HCl, 30 mL volume should be used.
Answer:
Proxima Centuri is 9 orders of magnitude further from New York compared to Perth
Explanation:
Distance of Proxima Centuri to New York = 4 × 10^16 meters
Distance of Proxima Centuri to Perth = 11000 miles
Since 1 mile = 1609 meters, distance to Perth in meters = 11000 × 1609
Distance to Perth = 17699000 = 1.7699 × 10^7 meters
Order of magnitude of the distances of Proxima Centuri to New York and Perth = 10^16/10^7
Order of magnitude = 10^9
Therefore, Proxima Centuri is 9 orders of magnitude further from New York compared to Perth.
Answer:
Explanation:
mass of the reactant = mass of the product
15.31 + 1.50 = 16.81g
