4. It is an endothermic process. The body of someone taking a shower would be absorbing heat from the environment, another example of this would be cooking an egg
5. Ice melting is endothermic. The ice is absorbing heat from the environment, water freezing would be an exothermic reaction as it is transferring heat into the environment
6 however i do not have an answer for. I may just be a little dense but I'm not entirely sure what it is asking when it asks what the system is.
Answer:
pH = 8.48
Explanation:
HOBr dissociates in water as follows:
- HOBr(aq) ↔ H⁺(aq) + OBr⁻(aq)
With a ka expressed by:
- ka = [H⁺]*[OBr⁻] / [HOBr]
We rearrange and <u>solve for [H⁺]</u>:
- [H⁺] = ka * [HOBr] / [OBr]
Because the volume is 1 L, the moles added of HOBr and KOBr (OBr⁻) are also the molar concentration:
- [H⁺] = 2.0x10⁻⁹ * 0.50 / 0.30
Finally we <u>calculate the pH</u>:
1. To make steel
2. It's salts are used to treat anaemia.
3. Pure iron is used in magnets.
4. It is used as a catalyst in the Haber Process which makes ammonia.
5. A very pure iron called wrought iron is used for ornamental gates or fences.
Answer:
Molar mass = 32.64 g / mol.
The density of gas is 1.3 × 10⁻³g/mL.
Explanation:
Given data:
Mass of sample = 2.35 g
Pressure = 1.05 atm
Volume = 1.85 L (1.85 × 1000 = 1850 ml)
Temperature = 55 °C (55+ 273.15 = 328.15 K)
Density = ?
Formula:
d = m/ v
The volume of flask would be the volume of gas.
d = 2.35 g / 1850 mL = 0.0013 g/mL or 1.3 × 10⁻³g/mL
The density of gas is 1.3 × 10⁻³g/mL.
Molar mass:
Now we will calculate the moles of a gas first in order to find the molar mass of a gas.
Formula:
PV =nRT
n = number of moles.
n = PV / RT
n = 1.05 atm × 1.85 L / 0.0821 atm. dm³. K⁻¹ . mol⁻¹ × 328.15 K
n = 1.9425 atm . L / 26.941115 atm . dm.³mol⁻¹
n = 0.072 mol
Now we will find the molar mass.
Number of moles = mass / molar mass
0.072 mol = 2.35 g / molar mass
Molar mass = 2.35 g / 0.072 mol
Molar mass = 32.64 g / mol
It doesnt, soap is comprised of water, and water and oil do not have the same molarity, therefore do not mix and will just continue to rub oil on your hand but not come off
