The formula for determination of atomic mass given the mass of isotopes and relative abundance is:
Ar = ∑(mass * abundance) / 100
Ar = (68.92558 * 60.108 + 70.92470 * 39.892) / 100
Ar = 69.72306
The atomic mass of gallium is 69.72306 amu
Answer:
Cool air moves down while hot air rises
Answer:
7
Explanation:
just add p has 1 o has 4 and h has 2
Q=mCdeltaT
Q=(640)(0.09)(375-26)
Q=20102.4J
Explanation :
Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.
The rule apply for the multiplication and division is :
The least number of significant figures in any number of the problem determines the number of significant figures in the answer.
The rule apply for the addition and subtraction is :
The least precise number present after the decimal point determines the number of significant figures in the answer.
(a) 628 × 342
![628\times 342=214776=2.15\times 10^5](https://tex.z-dn.net/?f=628%5Ctimes%20342%3D214776%3D2.15%5Ctimes%2010%5E5)
The correct answer is, ![2.15\times 10^5](https://tex.z-dn.net/?f=2.15%5Ctimes%2010%5E5)
(b) (5363 × 102) × (7.4 × 103)
![(5363\times 102)\times(7.4\times 103)=547026\times 762.2=(5.47\times 10^5)\times (7.6\times 10^2)=41.572\times 10^7=4.2\times 10^8](https://tex.z-dn.net/?f=%285363%5Ctimes%20102%29%5Ctimes%287.4%5Ctimes%20103%29%3D547026%5Ctimes%20762.2%3D%285.47%5Ctimes%2010%5E5%29%5Ctimes%20%287.6%5Ctimes%2010%5E2%29%3D41.572%5Ctimes%2010%5E7%3D4.2%5Ctimes%2010%5E8)
The correct answer is, ![4.2\times 10^8](https://tex.z-dn.net/?f=4.2%5Ctimes%2010%5E8)
(c) 28.0 ÷ 13.483
![\frac{28.0}{13.483}=2.08](https://tex.z-dn.net/?f=%5Cfrac%7B28.0%7D%7B13.483%7D%3D2.08)
The correct answer is, 2.08
(d) 8119 × 0.000023
![8119\times 0.000023=0.186737=1.9\times 10^{-1}](https://tex.z-dn.net/?f=8119%5Ctimes%200.000023%3D0.186737%3D1.9%5Ctimes%2010%5E%7B-1%7D)
The correct answer is, ![1.9\times 10^{-1}](https://tex.z-dn.net/?f=1.9%5Ctimes%2010%5E%7B-1%7D)
(e) 14.98 + 27,340 + 84.7593
![14.98+27340+84.7593=27439.7393=2.744\times 10^4](https://tex.z-dn.net/?f=14.98%2B27340%2B84.7593%3D27439.7393%3D2.744%5Ctimes%2010%5E4)
The correct answer is, ![2.744\times 10^4](https://tex.z-dn.net/?f=2.744%5Ctimes%2010%5E4)
(f) 42.7 + 0.259
![42.7+0.259=42.959=43.0=4.30\times 10^1](https://tex.z-dn.net/?f=42.7%2B0.259%3D42.959%3D43.0%3D4.30%5Ctimes%2010%5E1)
The correct answer is, ![4.30\times 10^1](https://tex.z-dn.net/?f=4.30%5Ctimes%2010%5E1)