Answer:
Option A.
2Na + 2H2O —> 2NaOH + H2
Explanation:
To know which option is correct, we shall do a head count of the number of atoms present on both side to see which of them is balanced. This is illustrated below below:
For Option A:
2Na + 2H2O —> 2NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 2 Na
4 H >>>>>>>>>>>> 4 H
2 O >>>>>>>>>>>> 2 O
Thus, the above equation is balanced.
For Option B:
2Na + 2H2O —> NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 1 Na
4 H >>>>>>>>>>>> 3 H
2 O >>>>>>>>>>>> 1 O
Thus, the above equation is not balanced.
For Option C:
2Na + H2O —> 2NaOH + H2
Reactant >>>>>>> Product
2 Na >>>>>>>>>>> 2 Na
2 H >>>>>>>>>>>> 4 H
1 O >>>>>>>>>>>> 2 O
Thus, the above equation is not balanced.
For Option D:
Na + 2H2O —> NaOH + 2H2
Reactant >>>>>>> Product
1 Na >>>>>>>>>>> 1 Na
4 H >>>>>>>>>>>> 5 H
2 O >>>>>>>>>>>> 1 O
Thus, the above equation is not balanced.
From the illustrations made above, only option A is balanced.
Answer:
112 mL
Explanation:
The formula for percent by volume is
If you have 250 mL of a solution that is 44.8 % v/v,
C. carbon
sodium is an
oxygen is o
cl is chlorine
Density is the measure of a material's mass per unit volume, used in many aspects of science, engineering and industry. Density can be calculated by dividing an object's mass by its volume. Since different materials have different densities, measuring an object's density can help determine which materials are in it. Finding the density of a metal sample can help to determine its purity.When measuring liquids and regularly shaped solids, mass and volume can be discovered by direct measurement and these two measurements can then be used to determine density. Using a pan balance, determine and record the mass of an object in grams. Using a vernier caliper or ruler, measure the length, depth and width of the object in centimeters. Multiply these three measurements to find the volume in cubic centimeters. Divide the object's mass by its volume to determine its density. Density is expressed in grams per cubic centimeter or grams per milliliter.
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