Answer:
2.40 M
Explanation:
The molarity of a solution tells you how many moles of solute you get per liter of solution.
Notice that the problem provides you with the volume of the solution expressed in milliliters,
mL
. Right from the start, you should remember that you must convert this volume to liters by using the conversion factor
1 L
=
10
3
mL
Now, in order to get the number of moles of solute, you must use its molar mass. Now, molar masses are listed in grams per mol,
g mol
−
1
, which means that you're going to have to convert the mass of the sample from milligrams to grams
1 g
=
10
3
mg
Sodium chloride,
NaCl
, has a molar mass of
58.44 g mol
−
1
, which means that your sample will contain
unit conversion
280.0
mg
⋅
1
g
10
3
mg
⋅
molar mass
1 mole NaCl
58.44
g
=
0.004791 moles NaCl
This means that the molarity of the solution will be
c
=
n
solute
V
solution
c
=
0.004791 moles
2.00
⋅
10
−
3
L
=
2.40 M
The answer is rounded to three sig figs, the number of sig figs you have for the volume of the solution.
Mass of metal piece is 611 g and volume of graduated cylinder is 25.1 mL. When metal piece is placed in the graduated cylinder water level increases to 56.7 mL. The increase in volume is due to volume of metal piece that gets added to the volume of water.
Thus, volume of metal piece can be calculated by subtracting initial volume from the final one.
Thus, volume of metal piece will be 31.6 mL. The mass of metal piece is given 611 g, density of metal can be calculated as follows:
Therefore, density of metal is 19.33 g/mL.
Hi :)
The bottom number tells you how many protons you have in the nucleus of this element.
In Krypton-84, this means that you have 84 nucleons, where 36 of these are protons, and the remaining 48 are neutrons.
Hope this helps :)
Answer:
I = 1.23 A
Explanation:
Given that,
The resistance of the lightbulb, R = 96.8 Ω
Voltage, V = 120 V
We need to find the current flows through the lightbulb. Let the current be I. We can use the ohm's law to find it i.e.
So, the current flows through the bulb is 1.23 A.
Chemical changes only happen when the object changes form. Color is a physical property because you're not changing the object that you have, compressibility is also a physical property because you still have the same substance before and sfter, malleability again is another physical. Heat of combustion is physical, when you burn things it changes the substance. :)
