Subscripts are used in a chemical formula to show the number of atoms of each element.
True or False.
If endothermic means that the temperature increases and exothermic means it decreases, it 64 degrees to 64 degrees (it stayed the same) endothermic or exothermic?

Answers

Answer 1
False exothermic creates heat endothermic create cold
Answer 2

Answer:

The answer is none of them.

Explanation:

I did the study guide...Also, if it has no change, it is neither.


Related Questions

__Hgo > __Hg + __O2?​

Answers

How to Balance:

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

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

Answers

Answer:

ERosion i think

Explanation:

Answer:  

Deposition

Explanation:

I hope you have a nice day(:

Which sample matter is a pure substance

Answers

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:

which gas is the most dense under standard temperature and pressure?
A. H2
B. Ne
C. Ar
D. O2

Answers

Answer:

I think it's b: ne

Explanation:

its just a wild guess

What type of bond is present between Magnesium and Fluoride in MgF2?

Answers

Answer: Ionic Bond

Explanation:

Ionic compounds are created by bonding a metal and non-metal

Mg is a metal

Fluoride is a non-metal

an atom has 79 protons, 78 electrons and a mass number of 118. how many neutrons does this atom have​

Answers

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.

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

Answers

Answer:

b

Explanation:

dueto isotopes haveno thesame neutral numbee hence b iscorrect

Answer:

b

Explanation:

How do I find the hydrated formula?

Answers

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:

how did domestication of early crops start?​

Answers

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!

What is the volume of 26.1 g of a substance if the density of the substance is 0.28 g/mL?

Answers

Answer:

It is 93.2

Explanation:

It's that answer because if you divide volume and density that's what you get

Sodium chloride can be used to preserve meat because​

Answers

Answer:

Salt is effective as a preservative because it reduces the water activity of foods. .

The state of matter of a material depends on its
O A) density
OB) temperature
O C) volume
OD) weight

Answers

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

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.​

Answers

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

what is the energy level of aluminum​

Answers

Answer:

Three energy levels

The Bohr model for aluminum shows its thirteen protons and neutrons inside the nucleus, with thirteen electrons orbiting in three energy levels.

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

Answers

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

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

Answers

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.

How many grams of F are in 225 g CaF2?

Answers

Answer:

109.575

Explanation:

TO THE F TO 225 G Caf2 iys is 1233333.9999

When an objects volume is made smaller and it’s mass remains the same it’s density

Answers

Density decreases when volume increases if mass is kept constant. Density is defined as mass divided by volume.

Write the balanced chemical equation for the decomposition of sulfur trioxide to sulfur dioxide and
oxygen.

Answers

Answer:

The balanced equation is 2SO2+O2→2SO3 .

Which of the following molecules has a trigonal pyramidal shape?
CO
Ni ---CO
A.
СО
OBCI-S c
Xeo
O.
O C.
0-N

Answers

Answer:

Xeo

Explanation:

A is the molecules with the trigonal pyramid shape

How many grams of lithium hypochlorite (LiClO) are there in 0.649 mol ?

Answers

Answer:

37.9 or 38 grmas approximately

How many atoms of N (nitrogen) are there in 1 mole of NH4Cl?

Answers

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.

What molar concentration of hydrochloric acid (HCl) is needed to prepare a disinfectant solution with a pH

Answers

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]

What is the molecular geometry of the atoms bonded to the carbon atom indicated with arrow I in this structure of caffeine?

Answers

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.

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.

Answers

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.

Lollll I need help with this question

Answers

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

what is the formula for zinc sulfide

Answers

Answer:

the formula for zinc sulfide is b. ZnS

Order: Vitamin K (Aquamephyton) 1 mg IM x 1 dose Newborn: Weight 4 kg Supply: 10mg/mL vial How many mLs would be given

Answers

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.

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!

Answers

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 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

Answers

Answer:a, c, d

Explanation: just did it on edge

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The right of citizens of the United States to vote shall not be denied or abridged by the United States or by any State on account of race, color, or previous condition of servitude."- Fifteenth Amendment to the United States ConstitutionThis amendment was created primarily for the purpose ofA) punishing southern states. B) avoiding another Civil War. C) pardoning Confederate veterans. D) granting former slaves suffrage. As a college student, you are no doubt concerned about the grades that you earn while completing your coursework. If you wanted to know how overall GPA is related to success in life after college, how would you choose to approach this question and what kind of resources would you need to conduct this research? 5. Drew had $48 in his savings account. Eachweek he added $8 to his account. Stacie had$87 in her account. Each week she took $5out. After how many weeks will they have thesame amount of money in their savingsaccounts? Does Depressants slows down the body reactions?What is the most common drug among students ages 13- 21.Slow down the body's reactions, decrease heart & breath rates, lower blood pressure, relax muscles & relieve tension. *DepressantsAmphetaminesStimulantsNarcoticsdont ansewr if you just want points tysm !!! The figure below shows a hexagonal prism. Imagine a cross-section of the prism formed by a plane that is perpendicular to the bases of the prism. What must be true about the cross section. in the excerpt from texas v johnson majority opinion what is justice brennan's major claim What was one of the major effects of the end of the Civil War in the Indian Territory? A. The Five Tribes were forced to assimilate to American lifestyles. B. The Five Tribes had to cede portions of their land to the Union to make room for railroads. C. The Five Tribes were forced to give up ranching in favor of small-scale farming. D. The Five Tribes had to send their leaders to Washington to be tried for treason. Please select the best answer from the choices provided A B C D what is the voice of an unseen narrator Use the figure to find the measure of angle 2 Mitchell needs to buy some wood to build a rectangular box that is 12 inches long, 8 inches wide, and 10 inches high. How many square inches of wood would Mitchell need to build the box? Select all that apply.Which of the following are not reasons why Savannah surrendered to Sherman?Sherman was old friends with the mayor of Savannah.There were loyal union sympathizers in control of the city.To avoid destruction like the rest of the state.There were no troops to defend the city. At the end of the current year, Leer Company reported total liabilities of $315,000 and total equity of $115,000. The company's debt ratio on the last year-end was: all the elements are found on earth, where were they formed?1. in the sun2. in ancient stars3. in earths core4. in the gas cloud that formed earth What is a synonym for point of view? Read this excerpt from Common Sense.According to Paine, what does the king in Englanddo? Check all of the boxes that apply. a) fight warsb) give away landc) worship his peopled) make the country poor Which expression is equivalent to the expression(2x + 4)(x - 6)? The packages of wrapping paper cost $2.75 per package. At the last moment, Sally notices gift bags that cost $4. 99. Is it cheaper to wrap the CD or put it in a gift bag? Explain your answer. Find the slope of the line through each pair of points.(1,19) , (1,-7) Explain why the equation 6x+3=6x5 has no solutions. 1+1try to guess :) you will get 33 points