Answer:
5 environmental factors are
- Exposure to hazardous substances in the air, water, soil, and food.
- Natural and technological disasters.
- Climate change.
- Occupational hazards.
- The built environment.
Explanation:
<span>Answer: 6.1 g of Ca(NO₃)₂•4H₂O and 5.5 g of KIO₃
</span>
<span>Explanation:
</span>
1) Calculate the number of moles of <span>Ca(NO₃)₂ in 10.0 g
</span>
i) molar mass of <span>Ca(NO₃)₂ = 40.1 g/mol + 2x126.9 g/mol + 2x3x16.0 g/mol = 389.9 g/mol
</span>
<span>ii) Formula: number of moles = mass in grams / molar mass
</span>number of moles = 10.0 g / 389.9 g/mol = 0.02565 moles of Ca(NO₃)₂
<span>
</span><span>2) Write the chemical equation to state the mole ratio:</span>
<span />
<span>i) Ca(NO₃)2•4H₂O(s) + 2KIO₃(s) --> Ca(IO₃)₂(s) + 2KNO₃ + 4H₂O
</span>
ii) mole ratio: 1 mol Ca(NO₃)2•4H₂O(s) : 2 mol KIO₃(s) : 1 mol <span>Ca(IO₃)₂(s)
</span>
3) Use proportionality to find the actual number of moles
<span>
</span><span>i) </span>Ca(NO₃)₂•4H₂O(s)
1 mol <span>Ca(NO₃)₂•4H₂O(s) / 1 mol Ca(IO₃)₂ = x / 0.02565 mol Ca(IO₃)₂ => x = 0.02565 mol </span>Ca(NO₃)₂•4H₂O(s)
molar mass of <span><span>Ca(NO₃)₂•4H₂O(s)</span> = 40.0g/mol + 2x14.0g/mol + 2x3x16.0g/mol + 4x18.0g/mol = 236.0g/mol
</span>
<span>mass in grams = number of moles x molar mass = 0.02565 mol x 236.0 g/mol = 6.1 g
</span>ii) KIO₃
<span />
<span>1mol KIO₃/1molCa(IO₃)₂ = x / 0.02565 mol Ca(IO₃)₂ => x = 0.02565 mol KIO₃</span>
<span>molar mas of KIO₃ = 39.1 g/mol + 126.9 g/mol + 3x16.0 g/mol = 214.0 g/mol
</span>
mass in grams = 0.02565 mol x 214.0 g/mol = 5.5 g
The molecular formula tell us what elements the atoms are, and how many moles and atoms are attributed toward each element.
The molecular model tells us how the atoms/elements are bonded together.
Molecular formula : CH4
H
l
Molecular model: H -- C -- H
l
<span> H</span>