You can solve this problem through dimensional analysis.
First, find the molar mass of NaHCO3.
Na = 22.99 g
H = 1.008 g
C = 12.01 g
O (3) = 16 (3) g
Now, add them all together, you end with with the molar mass of NaHCO3.
22.99 + 1.008 + 12.01 + 16(3) = 84.008 g NaHCO3. This number means that for every mole of NaHCO3, there is 84.008 g NaHCO3. In simpler terms, 1 mole NaHCO3 = 84.008 g NaHCO3.
After finding the molar mass of sodium bicarbonate, now you can use dimensional analysis to solve for the number of moles present in 200. g of sodium bicarbonate.
Cross out the repeating units which are g NaHCO3, and the remaining unit is mole NaHCO3
200. * 1 = 200
200/ 84.008 = 2.38
Notice how there are only 3 sig figs in the answer. This is because the given problem only gave three sig figs.
Your final answer is 2.38 mol NaHCO3.
We can change the state of motion of an object by changing its speed, its direction of motion, or both. Acceleration is the rate at which the velocity is changing. In physics, the term acceleration applies to decreases as well as increases in speed.
Answer:
They cause boys' and girls' bodies to develop
Answer:
The activation energy of a chemical reaction is the energy that is required to be supplied for a chemical reaction to take place. The activation energy for the reaction of sodium is low compared to the energy released such that the reaction of sodium and water is spontaneous resulting in the melting of the sodium into liquid form
The activation energy of a candle wax is much higher, requiring the ignition of the wick which burns and in turn melts the candle wax to release vapors that burns alongside the wick to produce sooth carbon dioxide, carbon monoxide and water vapor and release of heat energy which also fuels further combustion of the candle wax and wick
Therefore, the activation energy of the candle wax and wick which require the heat of direct flame from an ignited matches is higher than the activation energy of sodium placed in a medium of water that reacts spontaneously without heat application
Explanation:
The answer is 267.93 g
Molar mass of CaBr2 is the sum of atomic masses of Ca and Br:
Mr(CaBr2) = Ar(Ca) + 2Ar(Br)
Ar(Ca) = 40 g/mol
Ar(Br) = 79.9 g/mol
Mr(CaBr2) = 40 + 2 * 79.9 = 199.8 g/mol
The percentage of Br in CaBr2 is:
2Ar(Br) / Mr(CaBr2) * 100 = 2 * 79.9 / 199.8 * 100 = 79.98%
Now make a proportion:
x g in 79.98%
335 g in 100%
x : 79.98% = 335 g : 100%
x = 79.98% * 335 g : 100%
x = 267.93 g