Answer:
108.43 grams KNO₃
Explanation:
To solve this problem we use the formula:
Where
- ΔT is the temperature difference (14.5 K)
- Kf is the cryoscopic constant (1.86 K·m⁻¹)
- b is the molality of the solution (moles KNO₃ per kg of water)
- and<em> i</em> is the van't Hoff factor (2 for KNO₃)
We <u>solve for b</u>:
- 14.5 K = 1.86 K·m⁻¹ * b * 2
Using the given volume of water and its density (aprx. 1 g/mL) we <u>calculate the necessary moles of KNO₃</u>:
- 275 mL water ≅ 275 g water
- moles KNO₃ = molality * kg water = 3.90 * 0.275
- moles KNO₃ = 1.0725 moles KNO₃
Finally we <u>convert KNO₃ moles to grams</u>, using its molecular weight:
- 1.0725 moles KNO₃ * 101.103 g/mol = 108.43 grams KNO₃
Water has the special type of attraction called Hydrogen bonding. The bonds between the Hydrogen and the Oxygen in each water molecule make a super dipole because the Oxygen atom is way more electronegative than the hydrogen atom. These OH bonds can then be attracted to other H2O molecules. If you have ever poured water up to the brim and there is little bit of water that is poking above the top, hydrogen bonding keeps those water molecules from spilling
1) same amount of carbon atoms.
That is why it is still called butane and butene.
but- always signifies 4 carbons
Answer:
2.29 × 10⁴ times
Explanation:
A single penny is 1.52 mm thick. The distance covered by 1 mole of pennies (6.02 × 10²³ pennies) is:
6.02 × 10²³ p × (1.52 mm/1 p) = 9.15 × 10²³ mm = 9.15 × 10²³ × 10⁻³ m = 9.15 × 10²⁰ m
The distance to the next nearest star other than our own (Alpha Centauri) is 4.22 light-years. Considering 1 ly = 9.46 × 10¹⁵ m, this distance in meters is:
4.22 ly × (9.46 × 10¹⁵ m/1 ly) = 3.99 × 10¹⁶ m
The times that the stack would go between the earth and Alpha Centauri are:
9.15 × 10²⁰ m / 3.99 × 10¹⁶ m = 2.29 × 10⁴