Answer:
B. 6.6%
Explanation:
The percentage error of a measurement can be calculated using the formula;
Percent error = (experimental value - accepted value / accepted value) × 100
In this question, the calibrated 250.0 gram mass is the accepted value while the weighed mass of 266.5 g is the experimental or measured value.
Hence, the percentage error can be calculated thus;
Percent error = (266.5-250.0/250.0) × 100
Percent error = 16.5/250 × 100
Percent error = 0.066 × 100
Percent error = 6.6%
Answer:
SI derived units
Other quantities, called derived quantities, are defined in terms of the seven base quantities via a system of quantity equations. The SI derived units for these derived quantities are obtained from these equations and the seven SI base units.
Explanation:
Hope this helps :D
Answer:
2 electrons will be needed by unbound oxygen in order to fill its 2nd shell.
Explanation:
The chemical reaction between magnesium and oxygen gives magnesium oxide as a product.The reaction is chemically represented as:

Magnesium is a metal of group-2 with 2 valence electrons.It has atomic number of 12.
![[Mg]=1s^22s^22p^63s^2](https://tex.z-dn.net/?f=%5BMg%5D%3D1s%5E22s%5E22p%5E63s%5E2)
In order to attain noble gas configuration it will loose two electrons.
![[Mg]^{2+}=1s^22s^22p^6](https://tex.z-dn.net/?f=%5BMg%5D%5E%7B2%2B%7D%3D1s%5E22s%5E22p%5E6)
...[1]
Oxygen is a non metal of group-16 with 6 valence electrons..It has atomic number of 8.
![[O]=1s^22s^22p^4](https://tex.z-dn.net/?f=%5BO%5D%3D1s%5E22s%5E22p%5E4)
In order to attain noble gas configuration it will gain two electrons.
![[O]^{2-}=1s^22s^22p^6](https://tex.z-dn.net/?f=%5BO%5D%5E%7B2-%7D%3D1s%5E22s%5E22p%5E6)
..[2]
2 electrons will be needed by unbound oxygen in order to fill its 2nd shell.
Answer:
original mass of the block of ice is 38.34 gram
Explanation:
Given data
cup mass = 150 g
ice temperature = 0°C
water mass = 210 g
water temperature = 12°C
ice melt = 2 gram
to find out
solution
we know here
specific heat of aluminum is c = 0.900 joule/gram °C
Specific heat of water C = 4.186 joule/gram °C
so here temperature difference is dt = 12- 0 = 12°C
so here heat lost by water and cup are given by
heat lost = cup mass × c × dt + water mass × C × dt
heat lost = 150 × 0.900 × 12 + 210 × 4.186 × 12
heat lost = 12168.72 J
so
mass of ice melt here = heat lost / latent heat of fusion
here we know latent heat of fusion = 334.88 joule/gram
so
mass of ice melt = 12168.72 / 334.88
mass of ice melt is 36.337554 gram
so mass of ice is here = mass of ice melt + ice melt
mass of ice = 36.337554 + 2
mass of ice = 38.337554 gram
so original mass of the block of ice is 38.34 gram