What might be useful for adding solids to a tube

Quais são as funções que o sangue desempenha em nosso organismo

TiliK225 [7]

Answer:

Explanation:

Blood is an essential part of the circulatory system in the human body. The main function of blood is that it helps to transport materials to different parts of the body where they are need. Blood helps carry waste materials of metabolism from where they are produced to the excretory system. It helps carry oxygen round the body system and it takes out carbon dioxide that is not needed by the body.

Some part of the blood sees to fighting foreign bodies in the system. They are called whiteblood cells. There is no immune system without the white blood cells.

5 0

3 years ago

1. About how many Atlantic horseshoe crabs were caught in 2017?

zimovet [89]

Answer:

994,491 were caught in 2017

6 0

3 years ago

In the operation of the Heat Transfer Service Unit, one of the variables you can control is the rate of cooling water flowing ag

max2010maxim [7]

Answer:

A. The rate of heat transfer through the material would increase.

Explanation:

To calculate the heat transfer in a heat exchanger you decide that there is not heat leakage to the surroundings, that means that magnitude of the two transfer rates will be equal. Any heat lost by the hot fluid, is gained by the cold fluid. The equation that describes this is Q = m×Cp×dT

Where:

heat = mass flow ×specific heat capacity × temperature difference

So if we increase the rate of flow of cooling water and the other variables that ypu can control remain the same, the result is that the rate of heat transfer through the material would increase, as it is stated in option a.

5 0

3 years ago

Read 2 more answers

Check all that apply.

White raven [17]

Answer:

4 for C in CH4

+4 for C in CO2

-2 for O in all substances

+1 for H in both CH4 and H2O

option 1,2,3 and 4 are correct. Option 5 is not correct

Explanation:

Step 1: Data given

Oxidation number of H = +1

Oxidation number of O = -2

Step 2: The balanced equation

CH4(g) + 2O2(g) → CO2(g) + 2H2O(g)

Step 3: The oxidation numbers

-4 for C in CH4

⇒ Oxidation number of H = +1

⇒ 4x +1 = +4

C has an oxidation number of -4

This is correct.

+4 for C in CO2

⇒ Oxidation number of O = -2

⇒ 2x -2 = -4

C has an oxidation number of +4

This is correct.

-2 for O in all substances

⇒ this is correct, the oxidation number of O is always -2 (except in H2O2 and Na2O2)

This is correct.

+1 for H in both CH4 and H2O

⇒ this is correct, the oxidation number of H is always +1 (except in metal hydrides).

This is correct.

+4 for O in H2O

⇒ Oxidation number of H = +1

⇒ 2x +1 = +2

The oxidation number of O is -2

This is not correct

5 0

3 years ago

How many grams of O2 are present in 44.1 L of O2 at STP?

ycow [4]

Taking into accoun the STP conditions and the ideal gas law, the correct answer is option e. 63 grams of O₂ are present in 44.1 L of O2 at STP.

First of all, the STP conditions refer to the standard temperature and pressure, where the values used are: pressure at 1 atmosphere and temperature at 0°C. These values are reference values for gases.

On the other side, the pressure, P, the temperature, T, and the volume, V, of an ideal gas, are related by a simple formula called the ideal gas law:

P×V = n×R×T

where:

P is the gas pressure.
V is the volume that occupies.
T is its temperature.
R is the ideal gas constant. The universal constant of ideal gases R has the same value for all gaseous substances.
n is the number of moles of the gas.

Then, in this case:

P= 1 atm
V= 44.1 L
n= ?
R= 0.082 $\frac{atmL}{molK}$
T= 0°C =273 K

Replacing in the expression for the ideal gas law:

1 atm× 44.1 L= n× 0.082 $\frac{atmL}{molK}$ × 273 K

Solving:

$n=\frac{1 atm x44.1 L}{0.082\frac{atmL}{molK}x273K}$

n=1.97 moles

Being the molar mass of O₂, that is, the mass of one mole of the compound, 32 g/mole, the amount of mass that 1.97 moles contains can be calculated as:

$1.97 molesx\frac{32 g}{1 mole}$ = 63.04 g ≈ 63 g

Finally, the correct answer is option e. 63 grams of O₂ are present in 44.1 L of O2 at STP.

Learn more about the ideal gas law:

brainly.com/question/4147359?referrer=searchResults

7 0

3 years ago