Household items that are substances

What quantity of heat is transferred when a 150.0g block of iron metal is heated from 25.0°C to 73.3°C? What is the direction of

s344n2d4d5 [400]

The direction of heat flow is increased which means blocks temperature is higher and hotter than it was before

3 0

2 years ago

The concentration of protein in a urine sample is calculated to be 2.77 μg/mL. What is the concentration of this solution in uni

maxonik [38]

Answer:

The concentration of this solution in units of pounds per gallon is $2.776*10^{-5} \frac{lb}{gal}$

Explanation:

Units of measurement are established models for measuring different quantities. The conversion of units is the transformation of a quantity, expressed in a certain unit of measure, into an equivalent one, which may or may not be of the same system of units.

In this case, the conversion of units is carried out knowing that 1 μg are equal to 2.205*10⁻⁹ Lb and 1 mL equals 0.00022 Gallons. So

$2.77 \frac{ug}{mL} = \frac{2.77 ug}{mL}$

If 1 μg equals 2.205*10⁻⁹ lb, 2.77 μg how many lb equals?

$lb=\frac{2.77ug*2.205*10^{-9}lb }{1ug}$

lb=6.10785*10⁻⁹

So, 2.77 μg= 6.10785*10⁻⁹ lb

Then:

$2.77 \frac{ug}{mL} = \frac{2.77 ug}{mL}=\frac{6.10785*10^{-9}lb }{mL} =\frac{6.10785*10^{-9}lb }{0.00022 gal} =\frac{6.10785*10^{-9}lb }{0.00022 gal}$

You get:

$2.77 \frac{ug}{mL} = 2.776*10^{-5} \frac{lb}{gal}$

The concentration of this solution in units of pounds per gallon is $2.776*10^{-5} \frac{lb}{gal}$

6 0

2 years ago

Part 1: A cylinder containing 20.0 L of compressed nitrogen is connected to an empty (evacuated) vessel with an unknown volume.

baherus [9]

Answer:

The volume of the vessel is 250 L

Partial pressure of hydrogen = 189 torr

Explanation:

Using Boyle's law

${P_1}\times {V_1}={P_2}\times {V_2}$

Given ,

V₁ = 20.0 L

V₂ = ?

P₁ = 25 atm

P₂ = 2 atm

Using above equation as:

${P_1}\times {V_1}={P_2}\times {V_2}$

${25}\times {20.0}={2}\times {V_2}$

${V_2}=\frac {{25}\times {20.0}}{2}\ L$

${V_2}=250\ L$

The volume of the vessel is 250 L.

According to Dalton's law of partial pressure:-

$P_{H_2}=Mole\ fraction\times Total\ Pressure$

So, according to definition of mole fraction:

$Mole\ fraction\ of\ H_2=\frac {n_{H_2}}{n_{H_2}+n_{He}}$

Also,

Mole fraction of H₂ = 1 - Mole fraction of He = 1 - 0.75 = 0.25

So,

Total pressure = 756 torr

Thus,

$P_{H_2}=0.25\times 756\ torr$

Partial pressure of hydrogen = 189 torr.

7 0

2 years ago

Place the following compounds in order of increasing vapor pressure. rubbing alcohol

adelina 88 [10]

Vapor pressure is the pressure which is exerted by the vapors of a liquid in equilibrium with the liquid. Vapor pressure depends on the boiling point; lower the boiling point higher will be the vapor pressure.

Based on the given compounds:

rubbing alcohol is polar and has the strongest intermolecular force of attraction followed by relatively polar ether and finally the non-polar propane.

The increasing order of boiling point will be:

propane < diethyl ether < rubbing alcohol

Thus, the increasing order of vapor pressure will be:

rubbing alcohol < diethyl ether < propane

Ans : F

7 0

2 years ago

What is the iupac name for this compound ch3-c(ch3) 2-ch2-chcl-ch3?

myrzilka [38]

The IUPAC name of the above mentioned compound is "2-Chloro-4,4-dimethylpentane"

Exaplanation:

Since the above organic compound is an compound with only one saturated bond, It can be considered as a single bond compound, and hence we can conclude that as alkane.
It also has 5 carbon atoms, so it is termed as pentane.
From right to left we have to number the atoms, and 2 nd carbon atom contain Cl atom so it is termed as 2-Chloro and in the 4th position carbon atom contains 2 methyl groups, so it is termed as, 2-Chloro-4,4-dimethylpentane.

4 0

2 years ago