Most chemical reactions involve the breaking and formation of chemical bonds. It takes energy to break a chemical bond but energy is released when chemical bonds are formed. If more energy is released than consumed, then the chemical reaction evolves heat and is said to be exothermic.
(Have a good day!)
Answer:
Most chemical reactions involve the breaking and formation of chemical bonds. It takes energy to break a chemical bond but energy is released when chemical bonds are formed. If more energy is released than consumed, then the chemical reaction evolves heat and it called exothermic.
what is the formula for fluoride?
Answer:Chemical formula F −
Molar mass 18.998403163 g·mol−1
Conjugate acid Hydrogen fluoride
Explanation:
Calculate the concentration of H3O⁺ in a solution that contains 1.8 × 10-5 M OH⁻ at 25°C. Identify the solution as acidic, basic, or neutral. A. 5.5 × 10-10 M, acidic B. 9.2 × 10-1 M, acidic C. 5.5 × 10-10 M, basic D. 1.8 × 10-10 M, neutral
Answer:
A. 5.5 × 10⁻¹⁰ M, acidic
Explanation:
Step 1: Given data
Concentration of H₃O⁺: 1.8 10⁻⁵ M
Step 2: Calculate the concentration of OH⁻
We will use the ionic product of water.
Kw = 1.0 × 10⁻¹⁴ = [H₃O⁺] × [OH⁻]
[OH⁻] = 1.0 × 10⁻¹⁴/[H₃O⁺] = 1.0 × 10⁻¹⁴/1.8 10⁻⁵ = 5.5 × 10⁻¹⁰ M
Step 3: Determine if the solution is acidic, basic or neutral
If [H₃O⁺] > 10⁻⁷ M, the solution is acidic.If [H₃O⁺] = 10⁻⁷ M, the solution is neutral.If [H₃O⁺] < 10⁻⁷ M, the solution is basic.Then, the solution is acidic.
21 Organs consist of cells and tissues that have been adapted to perform a specific function in living organisms. The stomach is a muscular organ that is located on the left side of the upper abdomen. The stomach secretes acid and enzymes that help in the digestion of food. In simple terms, the stomach is a digestive sac. Even though the stomach has an important role in food digestion, it cannot perform the process all on its own. It depends on other organs such as the salivary glands, esophagus, liver, and intestines to help complete the process. Each organ has its own specific job, but together they make up an organ system. An organ system is a group of organs that work together to perform one or more functions. Which of the following describes the role of the immune system in the body? A. It gets rid of wastes that the body produces. B. It uses electrical signals to control body functions. C. It uses chemical messages to control body functions. D. It gets rid of pathogens that invade the body.
Answer:
The correct answer is - D. It gets rid of pathogens that invade the body.
Explanation:
Like all other organ systems, the immune system is an organ system that involves several special organs that helps in fighting any foreign object or infection that invades our body. This organ system produces specific cells or chemicals to fight or kill the microbes, and unnatural change takes place in the body.
The organs involved in the immune system are lymphocytes or white blood cells, the complement system, antibodies, the lymphatic system the thymus, bone marrow, and the spleen.
All these combinedly helps in fighting, killing the microbes or infections that occur in the body, and correct the physiological changes that occur in the body to get rid of pathogens that invade the body.
5.50 L of a 0.190 M CaCl2M CaCl2 solution
How do you find Grams?
Answer:
115.891
Explanation:
Molarity is equal to moles/liters so to get moles we multiply molarity by liters, after this we multiply the moles by the total atomic weight of the compound to get grams
how do the polarization make the cell defective
Answer:
Batteries convert chemical energy into electrical energy. Polarization is a defect that occurs in simple electric cells due to the accumulation of hydrogen gas around the positive electrode. In simple cells, hydrogen gas is evolved as a result of chemical reactions taking place inside the cell
A 16 gram sample of O2(g) fills a container at STP.
What volume is the container?
Answer:
V = 11.2 L
Explanation:
Hello there!
In this case, according to the ideal gas equation:
[tex]PV=nRT[/tex]
It is possible to compute the volume as shown below:
[tex]V=\frac{nRT}{P}[/tex]
Whereas the moles are computed are computed given the mass and molar mass of oxygen:
[tex]n=16g*\frac{1mol}{32g} =0.5mol[/tex]
Now, since the STP stands for a temperature of 273.15 K and a pressure of 1 atm, the resulting volume is:
[tex]V=\frac{0.5mol*0.08206\frac{atm*L}{mol*K}*273.15K}{1atm}\\\\V=11.2L[/tex]
Best regards!
Graphite, an allotrope of carbon, is converted into cubic diamond through a process that may take a billion years or longer. As illustrated above, scientists can make synthetic diamonds using a certain process in about one week. However, these synthetic diamonds have carbon atoms in a hexagonal lattice. Diamonds with a carbon atoms in a cubic lattice are not produced even though they are thermodynamically more stable than hexagonal diamond. Which of the following best justifies why the synthetic process produces hexagonal diamond and not the more thermodynamically stable cubic diamond?
a. The amount of energy required to create new bonds between carbon atoms in cubic diamond is much greater than the amount of energy required to create hexagonal diamond.
b. The amount of energy required to create new bonds between carbon atoms in cubic diamond is much smaller than the amount of energy required to create hexagonal diamond.
c. The activation energy needed to form cubic diamond is much less than the activation energy needed to form hexagonal diamond.
d. The activation energy needed to form cubic diamond is much greater than the activation energy needed to form hexagonal diamond.
Answer:
The activation energy needed to form cubic diamond is much greater than the activation energy needed to form hexagonal diamond.
Explanation:
The activation energy refers to the minimum energy that reacting species must possess before they can undergo a particular chemical reaction.
This implies that if species do not possess the activation energy, they hardly undergo a given reaction. The activation energy is the barrier between reactants and products.
Hence, a reaction that has a very high activation energy occurs slowly or may not even occur. The activation energy needed to form cubic diamond is much greater than the activation energy needed to form hexagonal diamond hence the synthetic process produces hexagonal diamond and not the more thermodynamically stable cubic diamond.
2. Seed color--- a. Yellow is dominant (Y) b. Green is recessive (y) c. A yy father and a yy mother d. What color(s) are the parents? e. What color(s) are the children?
Answer:
The parents are green and the children are green.
Explanation:
They all have the green recessive (y). So, the parents are green and the children are green.
Olive oil has a smoke point of 191 degree celsius and soybean oil has a smoke point of 238 degree celsius. With this in mind, explain why olive oil is better used for sautes as compared to soybean oil which is better for deep frying?
Answer:
It does not disintegrate at high temperature
Explanation:
Because of its lower smoke point, lower saturated fat and higher unsaturated fats, are considered best for higher temperature tolerance.
It is so because olive oil unlike normal oils with low smoke point will not disintegrate at high temperature and hence it can be used for deep frying
_____ are the 14 transition metals that follow
lanthanum in the periodic table.
What is the blank
Answer:
Lanthanide or Lanthanides
Explanation:
sorry if this isent right, but i hope it helps
There are various kind of elements that are present in periodic table. Some elements are harmful, some are radioactive, some are noble gases. Therefore the correct option is Lanthanides and actinides.
What is periodic table?Periodic table is a table in which we find elements with properties like metals, non metals, metalloids and radioactive element arranges in increasing atomic number.
Periodic table is divided into blocks as s block, p block ,d block and f block. There are total two periods of f block elements. The one that comes in 6th period is called Lanthanides and one which is in 7th period is called actinides. Lanthanides and actinides are called inner transition element and contains 14 elements.
Therefore the correct option is Lanthanides and actinides.
Learn more about periodic table , here:
https://brainly.com/question/11155928
#SPJ2
What are characteristics of absorption spectra? Check all that apply.
Light is absorbed, which produces characteristic lines.
| Light is emitted, which produces characteristic lines.
Lines are dark on a visible light background.
Lines are brightly colored on a black background.
Lines are produced by electrons being excited.
Lines are produced from electrons returning to a lower energy level.
Answer:
Light is absorbed, which produces characteristic lines.
Lines are dark on a visible light background.
Lines are produced by electrons being excited.
Explanation:
Edg
The characteristics of absorption spectra light is absorbed, which produces characteristic lines, lines are dark on a visible light background and Lines are produced by electrons being excited.
What is absorption spectra?The term "absorption spectroscopy" applies to spectroscopic methods that assess how much radiation interacts with a sample and is absorbed as a proportion of frequency or wavelength. The sample takes in photons, meaning energy, from the emitting field.
What are electrons?The electron would be a subatomic particle with a negative one fundamental charge electric charge. Due to their lack of components or substructure, electrons, which have become part of the lepton particle family's first generation, could be typically regarded to be elementary particles.
The percentage of incoming electromagnetic energy that a material absorbs across a variety of frequencies is displayed in the material's absorption spectrum. In a way, an emission spectrum would be the converse of an absorption spectrum.
To know more about absorption spectrum and electrons
https://brainly.com/question/1255220
#SPJ2
6. What is the number of moles of KF in a 29 gram sample?
a. 59.0 mols
C. 2.0 mols
b. 470 mols
d. 1684.9 mols
A voltaic cell consists of a strip of cadmium metal in a solution of Cd(NO3)2 in one beaker, and in the other beaker a platinum electrode is immersed in a NaCl solution, with Cl2 gas bubbled around the electrode. A salt bridge connects the two beakers.
1. Which electrode serves as the anode, and which as the cathode?
a. Pt serves as the cathode, Cd as the anode.
b. Cd serves as the cathode, Pt as the anode
2. Does the Cd electrode gain or lose mass as the cell reaction proceeds?
3. Write the equation for the overall cell reaction.
4. What is the emf generated by the cell under standard conditions? E0= ? V
Answer:
b.
Explanation:
How much energy is needed to evaporate 100g of water
Answer: you would have to remove 80 calories from 1 g of pure water at the freezing point, 0˚ C, to convert it to 1 g of ice at 0˚ C. Explanation:However, 540 calories of energy are required to convert that 1 g of water at 100˚ C to 1 g of water vapor at 100˚ C. This is called the latent heat of vaporization. On the other hand, you would have to remove 80 calories from 1 g of pure water at the freezing point, 0˚ C, to convert it to 1 g of ice at 0˚ C.
How many atoms of Bi are there in a 41.8 g sample?
Answer:
The number of particles in the 41.8g sample of Bismuth is 12.044 × 10²³
Please answer this question correctly
Answer:
a d c a b b
Explanation:
22 Which of the following statements is true for all loving organisms? A. All living organisms are made of one or more cells with a cellular membrane and have a cell wall. B. All living organisms are made of one or more cells with a cellular membrane and have a nucleus. C. All living organisms are made of one ore more cells with a cellular membrane and genetic material. D. All living organisms are made of one or more cells with a cellular membrane and have chloroplast
Answer:
C
Explanation:
Ape-x
(d) Other
sugar molecules become
_____ and are carried away from the crystal.
the force of attraction is
Answer:
liquid
Explanation:
defiantly
A solution contains 6.30 x 10-2 g of oxalic acid, H2C204 - 2
H20, in 250 mL. What is the molarity (M) of this solution?
Answer: c= 1.99·10^-3 mol/l
Explanation: molar mass of oxalis acid is M=126.068 g/mol.
V= 0.25 l and mass is 0.063 g
Amount of substance n = m/ M = cV
Molality c = m/MV
What is the formula for manganese(III) oxide?
Explain.
Answer:
Mn2O3
Explanation:
Manga has a 3+ charge and oxygen has a 2- charge so to balance the charges there needs to be 3 oxygens for every 2 manga
what are the part of mosses
don't copy this
Transfer cells have convoluted cell walls that increase surface area for nutrient exchange. In most mosses the sporophyte will have these anatomical features: a foot, seta, a sporangium with a columella, spores, an operculum, peristome teeth, and a calyptra.
Answer:
Mosses lack true roots, but they do have grasping, rootlike structures called rhizoids. The aboveground parts can be delineated into two sections: the gametophyte and the sporophyte. The gametophyte is the base of the moss, with a stem and a soft cluster of leaves
Why is there not a constant molar volume for solids and
liquids?
a Solid and liquid particles are packed close together,
b The densities of solids and liquids are variable.
с
The volume of a solid or a liquid has very little
empty space.
d All of the above
Answer:
all of the above
Explanation:
i got the answer right on cK-12
Which product forms from the synthesis reaction between lithium (Li) and oxygen (O)?
A. Li2O
B. LiO
C. LiO2
D. Li2O2
Answer:
A Li2O
Explanation:
Li has a 1+ charge and O has a 2- charge so to balance the charges there needs to be 2 Li for every 1 O
The product forms from the synthesis reaction between lithium (Li)and oxygen (O) is Li₂O. The correct option is A.
What is synthesis reaction?
Synthesis reaction is the reaction when two or more products combine to form a single product.
An example of a synthesis reaction is the combination of sodium (Na) and chlorine (Cl) to produce sodium chloride (NaCl).
Thus, the correct option is A. Li2O.
Learn more about synthesis reaction
https://brainly.com/question/24936069
#SPJ2
PLSSS HELP ASAP!!!!!!!!
Answer:
i-dk but A seems most logical to me
Explanation:
List three aids with example that are useful for people who are optically impaired
please answer then I will mark you as brainliest
Please help
I need to turn in in 5 min
<3
If 75 g. of Potassium Chloride (ionic compound) is dissolved in 250 grams of
water, what will be the freezing point of the solution? Kf = 1.86
Answer:
[tex]T_{f,sol}=-15.0\°C[/tex]
Explanation:
Hello there!
In this case, for these problem about the colligative property of freezing point depression, it is possible set up the following equation:
[tex]T_{f,sol}-T_{f,water}=-i*m*Kf[/tex]
Whereas the van't Hoff's factor, i, is 2 since KCl is ionized in two ions (K+ and Cl-); and the molality (m) of the solution is computed by:
[tex]m=\frac{75g*\frac{1mol}{74.55g} }{250g*\frac{1kg}{1000g} } \\\\m=4.02mol/kg[/tex]
Thus, since the freezing point of water (ice) is 0°C, we obtain the following freezing point of the solution by plugging in:
[tex]T_{f,sol}=-(2)(4.02mol/kg)(1.86\°C/mol*kg)\\\\T_{f,sol}=-15.0\°C[/tex]
Best regards!
what is the speed of the electromagnetic waves please solve using correct units ill give brainliest.
Answer:
3 m
Explanation:
We'll begin by converting 99.9 MHz to Hz. This can be obtained as follow:
1 MHz = 10⁶ Hz
Therefore,
99.9 MHz = 99.9 MHz × 10⁶ Hz / 1 MHz
99.9 MHz = 99.9×10⁶ Hz
Finally, we shall determine the wavelength. This can be obtained as follow:
Frequency (f) = 99.9×10⁶ Hz
Velocity (v) = 3×10⁸ m/s
Wavelength (λ) =?
Velocity = wavelength × frequency
v = λf
3×10⁸ = λ × 99.9×10⁶
Divide both side by 99.9×10⁶
λ = 3×10⁸ / 99.9×10⁶
λ = 3 m
Thus, the wavelength of the electromagnetic wave is 3 m.
Is anyone good at chemistry if so can someone help me please ?
(NO LINKS)
Since pH + pOH = 14, given a pOH of 4.53, our pH would be 14 - 4.53 = 9.47. And since the pH is greater than 7, this solution is basic. So, the correct answer choice would be D.
Please disregard this
well i need points
Explanation:
thanks