Answer:
A. Eight
Explanation:
Although there are eight major endocrine glands scattered throughout the body, they are still considered to be one system because they have similar functions, similar mechanisms of influence, and many important interrelationships.
Measurements show that the enthalpy of a mixture of gaseous reactants increases by 319kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that 92kJ of work is done on the mixture during the reaction. Calculate the change of energy of the gas mixture during the reaction in kJ.
Answer:
the change in energy of the gas mixture during the reaction is 227Kj
Explanation:
THIS IS THE COMPLETE QUESTION BELOW
Measurements show that the enthalpy of a mixture of gaseous reactants increases by 319kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that -92kJ of work is done on the mixture during the reaction. Calculate the change of energy of the gas mixture during the reaction in kJ.
From thermodynamics
ΔE= q + w
Where w= workdone on the system or by the system
q= heat added or remove
ΔE= change in the internal energy
q=+ 319kJ ( absorbed heat is + ve
w= -92kJ
If we substitute the given values,
ΔE= 319 + (-92)= 227 Kj
With the increase in enthalpy and there is absorbed heat, hence the reaction is an endothermic reaction.
Help! I’ll give brainliest if u get it right!
Answer:
That is the Atomic mass
Explanation:
The element symbol is S, Element name is sulfur, and
Atomic number is 16
If a solution containing 24.0 g of a substance reacts by first-order kinetics, how many grams remain after three half-lives?
Answer:
3.0g remain
Explanation:
The half-life is defined as the time required for a reactant to decrease its concentration in exactly the half of the initial amount of reactant. Having this in mind:
In one half-life, the mass will be:
24.0g / 2 = 12.0g
In two half-lifes:
12.0g / 2 = 6.0g
And in three half-lifes, the mass that remain is:
6.0g / 2 =
3.0g remainWhat is the surface composition of planets in the solar system?
A,. Helium or hydrogen
B,. Rock or gas
C., Rock or water
D,. Water or helium
Answer:
A: Helium or Hydrogen
Explanation:
Terrestrial planets are the 4 inner most planets of the solar system which are mercury, venus, earth, Mars, while the giant planets are the 4 outer most which are Jupiter, Saturn, Uranus and Neptune.
Now, these outer most ones are the surface ones and are surrounded primarily by layers of hydrogen and helium gases.
5. Why is picric acid and tannic acid used in the treatment of burns?
Jane is sitting in the family car. Her mother is driving her from their house to the library. Jane waves as she passes her friend Marina. Which of the following is not moving with respect to Jane?
A. Marina
B. The family car
C.The library
D. Jane’s house
Answer:
B) The family car
Explanation:
I hope this helps :)
Rocks are classified on the basis of
Answer:
Rocks are classified according to characteristics such as mineral and chemical composition, permeability, texture of the constituent particles, and particle size. This transformation produces three general classes of rock: igneous, sedimentary and metamorphic. Those three classes are subdivided into many groups.
Explanation:
how many grams of na2co3 would be needed to produce 1000g of nahco3
Answer:
630.95 grams of Na₂CO₃ would be needed to produce 1000g of NaHCO₃
Explanation:
The balanced reaction is:
Na₂CO₃ + CO₂+ H₂O → 2 NaHCO₃
By stoichiometry of the reaction (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of each compound participate in the reaction:
Na₂CO₃: 1 moles CO₂: 1 moleH₂O: 1 mole NaHCO₃: 2 molesBeing the molar mass:
Na₂CO₃: 106 g/moleCO₂: 44 g/moleH₂O: 18 g/moleNaHCO₃: 84 g/moleThen by stoichiometry the following quantities of mass participate in the reaction:
Na₂CO₃: 1 mole* 106 g/mole= 106 gCO₂: 1 mole* 44 g/mole= 44 gH₂O: 1 mole* 18 g/mole= 18 gNaHCO₃: 2 moles* 84 g/mole= 168 gYou can apply the following rule of three: if 106 grams of Na₂CO₃ are needed to produce 168 grams of NaHCO₃, how much mass of Na₂CO₃ is necessary to produce 1000 grams of NaHCO₃?
[tex]mass of Na_{2} CO_{3}=\frac{1000grams ofNaHCO_{3} *106gramsofNa_{2} CO_{3} }{168grams ofNaHCO_{3}}[/tex]
mass of Na₂CO₃= 630.95 grams
630.95 grams of Na₂CO₃ would be needed to produce 1000g of NaHCO₃
When drawing a Bohr model for Sulfur, how many energy levels will you
draw?
5
4
3
2.
Answer:
3
Explanation:
2,8,6
Question 2 2 points)
Which of the atoms shown has an atomic number of 42
1
2
4
7
Answer:
4 is the answer
Explanation:
i am not sure for this question
Using the van der Waals equation, determine the pressure exerted by 4.30 mol Ar in 3.6 L at 325K.
Answer:
37.7 atm
Explanation:
Using the relation;
(P + an^2/V^2) (V - nb) = nRT
(P + an^2/V^2) = nRT/(V - nb)
a = 0.0341 atm dm^2 Mol^2
b = 0.0237 dm/mol
P = nRT/(V - nb) - an^2/V^2
P = [4.3 * 0.082 * 325 / (3.6 - (4.3 * 0.0237))] - (0.0341 * (4.3^2))/(3.6^2)
P = 114.595/(3.498) - 0.0487
P = 37.7 atm
To a flask, 15.0 mL of 1.25 M hydrofluoric acid is added. Then, 3.05 M NaOH is used to titrate the acid sample. Write the balanced net ionic equation for the acid-base reaction.
HF(aq) + OH^- → H2O(I) + F^-
Answer:
H^+(aq) + OH^-(aq) --------> H2O(l)
Explanation:
We must first obtain the molecular equation, the net ionic equation before we obtain the net ionic equation.
The molecular reaction equation is;
HF(aq) + NaOH(aq) -------> H2O(l) + NaF(aq)
The complete ionic equation is;
H^+(aq) + F^-(aq) + Na^+(aq) + OH^-(aq) --------> H2O(l) + Na^+(aq) + F^-(aq)
The net ionic equation is;
H^+(aq) + OH^-(aq) --------> H2O(l)
Both magnetic fields and electric fields can exert a force true or false?
Answer:
false
Explanation:
An electric field may do work on a charged particle, while a magnetic field does no work.
Calculate how many grams of BeCl2 are required to produce 0.52 grams of MnCl2
Answer:
65.0cp
Explanation:
What is the vapor pressure of a solution in which the mole fraction of the solute is 0.200 and the vapor pressure of the pure solvent is 100.0 torr? (Assume a single nonvolatile, nonelectrolyte solute).
a. 0 torr
b. 80.0 torr
c. 100.0 torr
d. 120.0 torr
e. 20.0 torr
Answer: The vapor pressure of a solution in which the mole fraction of the solute is 0.200 is 80.0 torr
Explanation:
As the relative lowering of vapor pressure is directly proportional to the amount of dissolved solute.
The formula for relative lowering of vapor pressure will be,
[tex]\frac{p^o-p_s}{p^o}=i\times x_2[/tex]
where,
[tex]p^0[/tex]= vapor pressure of pure solvent = 100.0 torr
[tex]p_s[/tex] = vapor pressure of solution = ?
i = Van'T Hoff factor = 1 for nonvolatile, nonelectrolyte solute
[tex]x_2[/tex] = mole fraction of solute = 0.200
[tex]\frac{100.0-p_s}{100.0}=1\times 0.200[/tex]
[tex]p_s=80.0torr[/tex]
The vapor pressure of a solution in which the mole fraction of the solute is 0.200 is 80.0 torr
What type of reaction
the following chemical reaction?
2C2H4O2 → C4H6O3 + H2O
Which food dyes in the diagram on the right only contain one colour?
( Science, Chromatography )
Is energy absorbed or released during cellular respiration?
Absorbed
Released
Answer:
Released
Explanation:
they convert into a form of energy that can be used by cells
the first step in mitosis is the separateion of each pair of chromosomes true or false?
Answer:
true
Explanation:
Prophase is the first stage in mitosis, occurring after the conclusion of the G2 portion of interphase. During prophase, the parent cell chromosomes which were duplicated during S phase condense and become thousands of times more compact than they were during interphase.