Answer: physical
Explanation: freezing and melting are physical changes.
Answer:
the answer is 30% if the atoms will change to a stable
Answer:
- <em>Hydration number:</em> 4
Explanation:
<u>1) Mass of water in the hydrated compound</u>
Mass of water = Mass of the hydrated sample - mass of the dehydrated compound
Mass of water = 30.7 g - 22.9 g = 7.8 g
<u>2) Number of moles of water</u>
- Number of moles = mass in grams / molar mass
- molar mass of H₂O = 2×1.008 g/mol + 15.999 g*mol = 18.015 g/mol
- Number of moles of H₂O = 7.9 g / 18.015 g/mol = 0.439 mol
<u>3) Number of moles of Strontium nitrate dehydrated, Sr (NO₃)₂</u>
- The mass of strontium nitrate dehydrated is the constant mass obtained after heating = 22.9 g
- Molar mass of Sr (NO₃)₂ : 211.63 g/mol (you can obtain it from a internet or calculate using the atomic masses of each element from a periodic table).
- Number of moles of Sr (NO₃)₂ = 22.9 g / 211.63 g/mol = 0.108 mol
<u>4) Ratio</u>
- 0.439 mol H₂O / 0.108 mol Sr(NO₃)₂ ≈ 4 mol H₂O : 1 mol Sr (NO₃)₂
Which means that the hydration number is 4.
The number of C atoms in 0.524 moles of C is 3.15 atoms.
The number of
molecules in 9.87 moles
is 59.43 molecules.
The moles of Fe in 1.40 x
atoms of Fe is 0.23 x 
The moles of
in 2.30x
molecules of
is 3.81.
<h3>What are moles?</h3>
A mole is defined as 6.02214076 ×
of some chemical unit, be it atoms, molecules, ions, or others. The mole is a convenient unit to use because of the great number of atoms, molecules, or others in any substance.
A. The number of C atoms in 0.524 mole of C:
6.02214076 ×
x 0.524 mole
3.155601758 atoms =3.155 atoms
B. The number of
molecules in 9.87 moles of
:
6.02214076 ×
x 9.87
59.4385293 molecules= 59.43 molecules
C. The moles of Fe in 1.40 x
atoms of Fe:
1.40 x
÷ 6.02214076 × 
0.2324754694 x
moles.
0.23 x
moles.
D. The moles of
in 2.30x
molecules of
:
2.30x
÷ 6.02214076 × 
3.819239854 moles=3.81 moles
Learn more about moles here:
brainly.com/question/8455949
#SPJ1
Answer:
mercury( specific heat=0.140j/gc)