Explanation:
option A skeleton system is correct option
hope this helps you !
Answer:
C
Explanation:
The answer is C because machines such as tractors and sprinklers are counted as technology, and are better examples than pesticides.
The most accurate means of determining the purity of a substance is through the use of analytical methods. These methods, widely used in different industries, mostly involve chemical analysis, which can pinpoint the presence, identity and amount of impurities in the sample. The most simple chemical methods include gravimetry and titration. There are also the more advanced light-based or spectroscopic methods, such as UV-VIS spectroscopy, nuclear magnetic resonance and infrared spectroscopy. Chromatographic methods, such as gas chromatography and liquid chromatography, can also be used. Other methods used in testing the purity include mass spectroscopy, capillary electrophoresis, optical rotation and particle size analysis.
-basically nerdy talk for using machines controlling chemicals or other atoms to pinpoint any impurities
There’s lots of measurements. (m, kg, s, mol, cm, in, mm) etc
Answer:
28.11g
Explanation:
Step 1:
Background understanding:
From Avogadro's hypothesis, 1 mole of any substance contains 6.02x10^23 atoms. This also indicates that 1 mole of helium (He) contains 6.02x10^23 atoms.
1 mole of He = 4g
Step 2:
Determination of the mass of He that contain 4.23x10^24 atoms. This is illustrated below:
4g of He contains 6.02x10^23 atoms.
Therefore Xg of He will contain 4.23x10^24 atoms i.e
Xg of He = (4x4.23x10^24)/6.02x10^23
Xg of He = 28.11g
Therefore, 28.11g of He contains 4.23x10^24 atoms
