Answer:
chongus because he's the only good one
What molar concentration of hydrochloric acid (HCl) is needed to prepare a disinfectant solution with a pH
Answer:
The correct approach is "3.1×10⁻³ M".
Explanation:
As we know,
[tex]pH=-log[H_{3}O^+][/tex]
[tex]pH=2.5[/tex]
[tex][H_{3}O]^+= \ ?[/tex]
Now,
⇒ [tex]-log[H_{3}O]^+=2.5[/tex]
⇒ [tex][H_{3}O]^+=10^{-2.5}[/tex]
⇒ [tex]=3.1\times 10^{-3} \ M[/tex]
So that the needed molar concentration of HCL will be:
= [tex]3.1\times 10^{-3} \ M[/tex]
The state of matter of a material depends on its
O A) density
OB) temperature
O C) volume
OD) weight
Answer:
Tempature
Explanation:
Matter can move between any two states (or phases) of matter depending on the pressure and temperature conditions. ... The temperature of the melting and boiling points depend on the identity of the substance and the atmospheric pressure.
Also apex.
Answer:
temperature
Explanation:
an example here
ice
when its cold ice tends to stay as a solid but as the temperature rises the ice melts and turns into a liquid... with more heat the water will turn into gas
Lollll I need help with this question
Answer:
Waves are any vibration that transfers energy from place to place.
Explanation:
IM NOT SURE ABOUT THE VIBRATION BIT BUT I AM ABOUT THE ENERGY
Which pair of elements are most likely to form a molecular compound?
Nitrogen and Hydrogen
Calcium and Copper
Chlorine and Neon
Please help! I will mark brainliest if correct!
Answer: Two nonmetals.
Explanation:
Answer:The only pair of nonmetals is sulfur and fluorine.
Explanation:The pair of elements most likely to form a molecular compound with each other are two nonmetals.
Which of the following is a process that changes the composition of rocks from one material to another? (3 points) a Erosion b Deposition c Physical weathering d Chemical weathering
Answer:
ERosion i think
Explanation:
Answer:
Deposition
Explanation:
I hope you have a nice day(:
an atom has 79 protons, 78 electrons and a mass number of 118. how many neutrons does this atom have
Answer:
39
Explanation:
Electrons weigh almost nothing, so their mass doesn't really matter for these types of problems. Just subtract 118-79 to find the remaining mass which is for the neutrons.
what is the formula for zinc sulfide
Answer:
the formula for zinc sulfide is b. ZnS
12. (01.06 LC)
Which of the following is a property of a pure substance? (5 points)
It consists of different types of compounds.
It may have substances in different states of matter,
It is made up of a single element or type of compound,
Its components can be separated by employing physical methods.
Answer:
3rd one
Explanation:
dont have one, i think just think it makes most sense
Answer:It is made up of a single element or type of compound
Explanation: This answer is right because for something to be pure it has to only be made up of 1 thing.
Which of the following molecules has a trigonal pyramidal shape?
CO
Ni ---CO
A.
СО
OBCI-S c
Xeo
O.
O C.
0-N
Answer:
Xeo
Explanation:
A is the molecules with the trigonal pyramid shape
What is the volume of 26.1 g of a substance if the density of the substance is 0.28 g/mL?
Answer:
It is 93.2
Explanation:
It's that answer because if you divide volume and density that's what you get
Isotopes have
Question 1 options:
A)
different numbers of both protons and neutrons in their nuclei.
B)
a different number of neutrons in their nuclei.
C)
a different number of protons in their nuclei.
D)
a different number of electrons.
Question 2 (5 points)
An aqueous solution
Question 2 options:
A)
must contain three or more substances.
B)
is a single-phase heterogeneous mixture.
C)
has water as the solvent.
D)
has water as the solute.
Question 3 (5 points)
Which of the following is a homonuclear diatomic molecule?
Question 3 options:
A)
NH3
B)
CO
C)
2CO2
D)
H2
Question 4 (5 points)
Given a container of a solution of 5% HCl, all samples tested from this same bottle will have the same mass ratio of hydrogen to chlorine. This is an application of
Question 4 options:
A)
the law of conservation of energy.
B)
the law of multiple proportions.
C)
the law of conservation of mass.
D)
the law of constant composition.
Question 5 (5 points)
Elements in the same period
Question 5 options:
A)
have the same principal quantum number.
B)
form bonds with the same type of elements.
C)
have the same number of valence electrons.
D)
have the same number of protons.
Question 6 (5 points)
Which of the following contribute(s) to most of the mass of an atom?
Question 6 options:
A)
Neutrons only
B)
Protons and neutrons
C)
Protons and electrons
D)
Protons only
Question 7 (5 points)
In a certain chemical reaction, the bonds of the products contain more energy than the bonds of the reactants. For the reaction to occur, which of the following best describes what occurred?
Question 7 options:
A)
Energy was released, so the reaction is endothermic.
B)
Energy was released, so the reaction is exothermic.
C)
Energy was added, so the reaction is endothermic.
D)
Energy was added, so the reaction is exothermic
Question 8 (5 points)
A solution
Question 8 options:
A)
is a single-phase homogeneous mixture.
B)
must contain water.
C)
is always a liquid.
D)
can contain more than two phases.
Question 9 (5 points)
Which of the following is true of alloys?
Question 9 options:
A)
They can only be composed of metals.
B)
They must be held together by chemical bonds.
C)
They're liquid solutions.
D)
They must contain a metal.
Question 10 (5 points)
Which of the following best describes an atomic number? An element's identity is defined by its atomic number; this means it represents the number of
Question 10 options:
A)
electrons in the element.
B)
neutrons in its nucleus.
C)
protons plus neutrons in its nucleus.
D)
protons in its nucleus.
Question 11 (5 points)
Electrons in the outermost shell of an atom that are available to bond with the electrons of other atoms are
Question 11 options:
A)
cations.
B)
free electrons.
C)
valence electrons.
D)
anions.
Question 12 (5 points)
Main group elements have valence electrons in which suborbitals?
Question 12 options:
A)
d and f
B)
s and p
C)
p and f
D)
s and d
Question 13 (5 points)
Molecules have
Question 13 options:
A)
only kinetic energy.
B)
only potential energy.
C)
both potential and kinetic energy.
D)
neither kinetic nor potential energy.
Question 14 (5 points)
The majority of elements are
Question 14 options:
A)
metalloids.
B)
nonmetals.
C)
metals.
D)
inert.
Question 15 (5 points)
A student found the mass of an object to be 26.5 g. To find the volume, the student submerged the object in a graduated cylinder of water. Submerging the object in the water in the graduated cylinder increased the water level by 24.1 mL. The density of the object is
Question 15 options:
A)
1.0906 g/mL.
B)
0.909 g/mL.
C)
1.10 g/mL.
D)
1.1 g/mL.
Question 16 (5 points)
Mass and energy are conserved
Question 16 options:
A)
only in chemical changes.
B)
in chemical changes and physical changes.
C)
always in physical changes and sometimes in chemical changes.
D)
only in physical changes.
Question 17 (5 points)
Which of the following can't be broken down any further chemically?
Question 17 options:
A)
Compounds
B)
Elements
C)
Matter
D)
Molecules
Question 18 (5 points)
A/an _______ is the smallest unit of matter that has the characteristics of a chemical element.
Question 18 options:
A)
atom
B)
proton
C)
molecule
D)
electron
Question 19 (5 points)
The distance between consecutive peaks or troughs in a wave is
Question 19 options:
A)
frequency.
B)
displacement.
C)
amplitude.
D)
wavelength.
Question 20 (5 points)
The phase transition of dry ice (frozen carbon dioxide) to gas is an example of
Question 20 options:
A)
condensation.
B)
sublimation.
C)
deposition.
D)
vaporization.
I WILL GIVE BRAINLIEST IF YOU CAN ANSWER THEM
Answer:
b
Explanation:
dueto isotopes haveno thesame neutral numbee hence b iscorrect
Answer:
b
Explanation:
How many atoms of N (nitrogen) are there in 1 mole of NH4Cl?
Answer:
In one mole of NH₄Cl 6.022 × 10²³ atoms of N are present.
Explanation:
Given data:
Number of atoms of N = ?
Number of moles of NH₄Cl = 1 mol
Solution:
First we have to calculate the number of atoms in NH₄Cl .
There is only 1 mole of N in 1 mole of NH₄Cl .
Now we will calculate the number of atoms of nitrogen in one mole of N by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
1 mole of N = 6.022 × 10²³ atoms of N
Thus in one mole of NH₄Cl 6.022 × 10²³ atoms of N are present.
How many grams of F are in 225 g CaF2?
Answer:
109.575
Explanation:
How many grams of glycine amide should be added to 1.00 g of glycine amide hydrochloride to give 100 mL of solution with pH 8.00
Answer:
0.4235 g of glycine amide should be added
Explanation:
From the given information:
The equation of the reaction can be illustrated as:
[tex]BH^+ \to B^+ + H ^-[/tex]
where:
mass of glycine amide hydrochloride = 1.00 g
Suppose x be the amount of (in grams) of glycine amide that is required to be added; Then:
[tex][BH^+] = \dfrac{1.00 \ g}{110.54 \ gmol \times 0.100 L}[/tex]
[tex][BH^+]=[/tex] 0.0905 M
So, For [B} i.e, for glycine amide
[tex][B] = \dfrac{x \ g}{74.083 \ gmol \times 0.100 L}[/tex]
[B] = 0.135x M
∴
[tex]\dfrac{[B]}{[BH^+]}=\dfrac{0.135x \ M}{0.0905 \ M }}[/tex]
[tex]\dfrac{[B]}{[BH^+]}=1.49x[/tex]
The log of the above question can be computed as:
[tex]log _{10}\dfrac{[B]}{[BH^+]}=log _{10}1.49x[/tex]
[tex]pH = pK_a + log _{10} \dfrac{[B]}{[BH^+]}[/tex]
8.00 = 8.20 + [tex]log _{10}(1.49x)[/tex]
8.00 - 8.20 = [tex]log _{10}(1.49x)[/tex]
-0.20 = [tex]log _{10}(1.49x)[/tex]
1.49 x = [tex]10^{-0.20}[/tex]
1.49 x = 0.631
x = 0.631/1.49
x = 0.4235 g
Which sample matter is a pure substance
Answer:
Explanation:
If you have options, could you please tell me so I can further help you. If you just need an example then
Examples of pure substances include iron, steel, and water
Hope this helps (:
Answer
These are the following answers
A) zinc oxide
B) sugar dissolved in water
C) pond water
D) soil
Explanation:
What type of bond is present between Magnesium and Fluoride in MgF2?
Answer: Ionic Bond
Explanation:
Ionic compounds are created by bonding a metal and non-metal
Mg is a metal
Fluoride is a non-metal
Order: Vitamin K (Aquamephyton) 1 mg IM x 1 dose Newborn: Weight 4 kg Supply: 10mg/mL vial How many mLs would be given
Answer:
Volume(ml) of drug required = 0.1 ml
So, medicine is safe for this child.
Explanation:
Given:
Desired dose (D)= 1 mg
Dose in hand (H) = 10 mg
Quantity (Q) = 1 ml
Computation:
Volume(ml) of drug = [Desired medicine / medicine in hand] Quantity.
Volume(ml) of drug required = [1/10]1
Volume(ml) of drug required = 0.1 ml
So, medicine is safe for this child.
__Hgo > __Hg + __O2?
Hg + O2 → HgO
✅Word equation: Mercury + Oxygen gas → Mercury (II) oxide
✅ Type of Chemical Reaction: For this reaction we have a combination reaction.
✅ Balancing Strategies: To balance this equation it's probably easiest to begin by changing the coefficient in front of the HgO.
This is a combination reactions because the mercury (Hg) plus the oxygen gas (O2) come together to form the Mercury (II) oxide (MgO).
Hint-1
Hint-2
IamSugarBee
A black bear can run 35.0 mph how long will it take to run 1.95 x 10^4?
A. 129
B. 0.360
C. None of the above
D. 0.106
E. 13
Answer:
The correct answer is C. None of the above.
Explanation:
To determine how long the black bear will run, the distance it will travel must first be determined. Thus, the proposed calculation must be solved.
1.95 x 10 ^ 4
1.95 x 10 x 10 x 10 x 10
19.5 x 10 x 10 x 10
195 x 10 x 10
1950 x 10
19500
Thus, the bear will run 19,500 miles, so, running at 35 mph, it will take about 557 hours to run that distance (19,500 / 35).
which gas is the most dense under standard temperature and pressure?
A. H2
B. Ne
C. Ar
D. O2
Answer:
I think it's b: ne
Explanation:
its just a wild guess
The melting and boiling points of a group of elements decrease as you go down the group, while their reactivity increases.
a.. Are the elements from the first group or the second last group of the Periodic Table?
b ..Does this group consist of metals, metalloids, non-metals or a mix?
c.. Identify two elements in this group.
Answer:
a) first group
b) metals
c) K - potassium, Li - lithium
Explanation:
a) they are the alkali metals
b) they're alkali metals lol
c) just look at a periodic table :P
Write the balanced chemical equation for the decomposition of sulfur trioxide to sulfur dioxide and
oxygen.
Answer:
The balanced equation is 2SO2+O2→2SO3 .
How many grams of lithium hypochlorite (LiClO) are there in 0.649 mol ?
Answer:
37.9 or 38 grmas approximately
When an objects volume is made smaller and it’s mass remains the same it’s density
Which of the following describe glands? Check all that apply.
a structure that secretes substances through a duct
a thin layer that separates or connects structures inside the body
a structure that secretes hormones into the bloodstream
a structure usually made from connective and epithelial cells
Answer:a, c, d
Explanation: just did it on edge
how did domestication of early crops start?
Answer:
In the Fertile Crescent in the Middle East, cereal crops were first domesticated about 11,000 years ago. Generally, the first domesticated crops were annuals with big seeds or fruits. ... Humans began to transition from a hunter-gatherer culture to a settled farming society as domestication took place.
Please mark me brainliest!
Hope this helps God bless!
Match each term with its definition.
a. The position of an equilibrium always shifts in such a direction as to relieve a stress applied to the system.
b. A molecule that donates a proton when it encounters a proton acceptor.
c. Occurs when a reaction involving an acid and its conjugate base is combined with a second reaction involving a base and its conjugate acid.
d. It ionizes completely when dissolved in water.
e. The shift in the position of equilibrium caused by the addition of a participating ion.
f. It only partially ionizes when dissolved in water.
g. It is capable of acting as either an acid or a base depending upon the solute.
h. The act of self-ionization of a solvent to produce both a conjugate acid and a conjugate base.
i. A chemical species that bears both positive and negative charges.
1. Week electrolyte
2. Bronsted-Lowry acid
3. Neutralization
4. Amphoteric solvent
5. Zwitterion
6. Auto-protolysis
7. Strong acid
8. Le Chåtelier's principle
9. Common effect
Answer:
The position of an equilibrium always shifts in such a direction as to relieve a stress applied to the system -Le Chåtelier's principle
A molecule that donates a proton when it encounters a proton acceptor.- Bronsted-Lowry acid
Occurs when a reaction involving an acid and its conjugate base is combined with a second reaction involving a base and its conjugate acid.- Neutralization
It ionizes completely when dissolved in water.- Strong acid
The shift in the position of equilibrium caused by the addition of a participating ion.- Common ion effect
It only partially ionizes when dissolved in water.- Weak electrolyte
It is capable of acting as either an acid or a base depending upon the solute- Amphoteric solvent
The act of self-ionization of a solvent to produce both a conjugate acid and a conjugate base.- Auto-protolysis
A chemical species that bears both positive and negative charges.- Zwitterion
Explanation:
In the answer box we have various chemical terminologies and their definitions. In answering the question, you must carefully read through each definition, then check what option best matches that definition from the options provided.
Each definition applies only to one terminology as you can see in the answer above.
Sodium chloride can be used to preserve meat because
Answer:
Salt is effective as a preservative because it reduces the water activity of foods. .
What is the molecular geometry of the atoms bonded to the carbon atom indicated with arrow I in this structure of caffeine?
Answer:
Trigonal planar
Explanation:
If we look at the carbon atom indicated I in the image, we will discover that it is a carbon atom that is bonded to a nitrogen atom via a double bond.
Recall that an sp2 hybridized carbon atom has a trigonal planar geometry. When a carbon atom is sp2 hybridized, it is in a trigonal planar geometry as we can clearly see from the image.
How do I find the hydrated formula?
Answer:
In order to determine the formula of the hydrate, [Anhydrous Solid⋅xH2O], the number of moles of water per mole of anhydrous solid (x) will be calculated by dividing the number of moles of water by the number of moles of the anhydrous solid (Equation
Explanation: