Answer:
Metals in general have they chemical property of reacting with an acid. Zinc reacts with hydrochloric acid to produce hydrogen gas. This is a chemical property. Chemical change results in one or more substances of entirely different composition from the original substances.
<em>Answer:</em>
- 0.052301 km have 5 significant figure
- 400 cm have 1 significant figure
- 50.0 m have 3 significant figure
- 4500.01 ml have 6 significant figure
<em>Explanation:</em>
According to rules of significant figure
0.052301 km have 5 significant figure:
- Zero to the left of the first non zero digit not significant.
- Zero between the non zero digits are significant.
<em>400 cm have 1 significant figure:</em>
- Trailing zeros are not significant in numbers without decimal points.
<em>50.0 m have 3 significant figure:</em>
- Trailing zeros are significant in numbers when there is decimal points.
<em>4500.01 ml have 6 significant figure:</em>
- Zero between the non zero digits are significant.
A = mass number which is equal to the total number of protons + number of neutrons, Z= atomic number of any element which is also indicates Number of protons or number of electron in the given atom.
The formula to calculate neutron would be :
mass number - proton
31 - 15 = 16
Thus 16 neutrons are found in one atom of P
There are 4 atom in one molecule
Thus
4 atom /1 molecule * 9 molecule * 16 neutron / 1 atom
= 4*9*16= 576 neutrons
Answer:
Explanation:
Molar mass of Argon
= 35.96755 x .00337 + 37.96272 x .00063 + 39.96240 x .99600
= .12121 + .0239165 + 39.80255
= 39.95
Molar mass of silicon
27.97693 x .9223 + 28.97649 x .0467 + 29.97376 x .0310
= 25.803 + 1.35320 + .929
= 28.08
b )
No of atoms of Si in 78.2 g = 78.2 x 6.02 x 10²³ / 28.08
= 16.76 x 10²³ .
c )
42 Ar / 40 Ar = 1.05006
42 Ar / 39.95 = 1.05006
42Ar = 41.95
2 )
C₁₆H₁₅F₂N₃O₄S
Mol weight = 16 x 12 + 1 x 15 + 2 x 19 + 3 x 14 + 4 x 16 + 32
= 192 + 15 + 38 + 42 + 64+ 32
= 383
No of molecules = .078 x 6.02 x 10²³ / 383
= 1.226 x 10²⁰ molecules .
Answer:
oxygen is an element because it is a pure substance which cannot be split into simpler substances by chemical means
