Answer:
I think all of the above
Explanation:
Put as brainliest if you wish
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?
Answer:
The answer is none of them.
Explanation:
I did the study guide...Also, if it has no change, it is neither.
A person drops two objects from the same height. one object weighs 15 N and the other weighs 10 N
A The 10 N object has the same mass as the 15 N object
B The 15 N object has twice the mass of the 10 N object
C The 15 N object has more mass than the 10 N object
D The 10 N object has more mass than the 10 N object
The vaporization of Br2 from the liquid to the gas state requires 7.4 kcal/mol. write a reaction showing heat as a product or reactant
Answer:
Br₂(l) + ΔV → Br₂(g)
Explanation:
When a chemical or phase change occurs during a chemical process some heat is absorbed or released. For the process of vaporization of a substance, the heat (Usually required) is ΔV (How many energy is required for the process occurs).
In the vaporization of Br2 there are required 7.4kcal/mol, Δv. The reaction is:
Br₂(l) + ΔV → Br₂(g)What is matter?
A.
Anything that has energy
B.
Anything that changes volume
C.
Anything that takes up space
D.
Anything that produces heat
a b c or d no bull
Answer:
C. Anything That Takes Up Space.
Explanation:
How much MmHg are in 30.0 psi
Answer:
1551.45 MmHg
hope this helps :D
How for way is the Neptune from the sun
C2H6O
Percent Composition with work shown
Answer:
50 percent
Explanation:
percentage
Pleaseee helpppp this is thermal energy in 6th rade and i need it quick for a formal assesment!!!!!!
Answer:The answer is B my child
Explanation:
3.
What are valence electrons? How do you quickly determine the number of valence electrons an
atom has?
Answer:
Electrons that arent electrons
Explanation:
I teach chem
Answer:
Valence electrons are the electrons found in the highest and main energy level of the atom, being these responsible for the interaction between atoms of different species or between atoms of the same species. You can quickly determine these by looking at a periodic table like this one... Which is where the roman numbers come in and show the valence electrons. (THIS TABLE IS IN SPANISH, I hope you still recognize the symbols.) :))
In chemical reactions, what does the law of conservation of mass mean?
Group of answer choices
Matter is not created nor destroyed.
The total mass of the products is greater than the total mass of the reactants.
The total mass of the reactants is less that the total mass of the products.
Matter is not changed.
Answer
The law of conservation of mass states that mass in an isolated system is neither created nor destroyed by chemical reactions or physical transformations. According to the law of conservation of mass, the mass of the products in a chemical reaction must equal the mass of the reactants.
A deck of cards has dimensions 8.9cm x 5.72cm x 1.82 cm. What is the volume of the deck in cubic centimeters?
Answer:
92.65256 cm^3
Explanation:
To find this, we can simply multiply all three dimensions to get the answer in cubic centimeters, and we get the answer above. If you want to be more specific, we can go by the sigfig rule and the answer would be rounded to 93 cm^3.
Which properties of grains determine the texture of rocks? Check all that apply.
feel
pattern
color
shape
size
I will mark Brainlyest
Answer:
color shape and size
Explanation:
Convert 3564 to Scientific Notation:
*
Answer:
3564 = 3.564 x 10^3
Explanation:
i.e expresing the value in standard form.
In chemistry lab, a student measured the density of liquid ethanol is 0.789 g/mL. Represent its density in units of 1b /in3? (2.54 cm = 1 in., 2.205 lb = 1 kg)
A. 9.09 x 10+ 1b / in
B.4.42 x 10-1b / in?
OC.2.85 x 10-2 16 / in
D. 0.106 16 / in?
O E.5.86 x 10" 16/in3
Answer:
Option C is correct option = 2.85×10⁻² lb/in³
Explanation:
Given data:
Density in g/mL = 0.789
Density in lb/in³ = ?
Solution:
It is given that,
2.54 cm = 1 in
2.205 lb = 1 kg thus,
1 mL = 1 cm³
0.789 g/cm³ × 1 kg/ 1000 g × 2.205 lb/1 kg × (2.54 cm / 1in)³
2.85×10⁻² lb/in³
The density of liquid ethanol is 0.789 g/mL, which is equivalent to 0.0285 lb/in³.
A student measured the density of liquid ethanol to be 0.789 g/mL and we want to convert it to lb/in³. We will need a series of conversion factors.
What is a conversion factor?A conversion factor is an arithmetical multiplier for converting a quantity expressed in one set of units into an equivalent expressed in another.
Step 1: Convert 0.789 g/mL to lb/mLWe will use the following conversion factors:
1 kg = 1000 g.1 kg = 2.205 lb.0.789 g/mL × (1 kg/1000 g) × (2.205 lb/1 kg) = 1.74 × 10⁻³ lb/mL
Step 2: Convert 1.74 × 10⁻³ lb/mL to lb/in³We will use the following conversion factors:
1 mL = 1 cm³.1 in = 2.54 cm.1.74 × 10⁻³ lb/mL × (1 mL/1 cm³) × (2.54 cm/1 in)³ = 0.0285 lb/in³
The density of liquid ethanol is 0.789 g/mL, which is equivalent to 0.0285 lb/in³.
Learn more about unit conversion here: https://brainly.com/question/13016491
A 10.151 g sample of window cleaner containing ammonia was diluted with 39.466 mL of water. Then 4.373 g of solution was titrated with 14.22 mL of 0.1063 M HCl to reach a bromocresol green end point. Find the weight percent of NH3 (FM 17.031) in the cleaner.
Answer:
2.878 (w/w)%
Explanation:
The reaction of NH3 with HCl is:
NH3 + HCl → NH4Cl
That means 1 mole of ammonia reacts per mole of HCl. The moles of HCl that reacts = Moles of ammonia are:
14.22mL = 0.01422L * (0.1063mol HCl / L) = 0.001512 moles HCl = Moles ammonia
In mass:
0.001512 moles NH3 * (17.031g / mol) = 0.02574g of NH3 in the solution.
The concentration in weight percent of the diluted solution is:
0.02574g of NH3 / 4.373g * 100 = 0.5887 (w/w)%
This is the concentration of the diluted solution that was diluted from 10.151g to 10.151g + 39.466g = 49.617g
-Assuming density of water = 1g/mL-
The solution was diluted:
49.617g / 10.151g = 4.888 times.
That means the concentration of NH3 in the original cleaner is:
0.5887 (w/w)% * 4.888 =
2.878 (w/w)%What is another name for radioactive dating?
Answer:
radioisotope dating is another name
Answer:
Radiometric dating
Explanation:
hope that helps
HELPPP
Which of the following pairs of elements is most likely to permanently transfer one or more electrons to the
other element?
a. Chlorine and phosphorus
b. Iron and bromine
c. Tin and lead
d. Nitrogen and oxygen
Why do you think the hot red water sank to the bottom?
Answer:
i did this in school :) but Hot water will rise to the top because it is less dence and cold water will sink to the bottom because it is more dence
Explanation:
Each orbit of an atom contains a set number of..........
Answer:
I'm pretty sure it's electrons
Describe the function of a cilia.
Answer:
hope it helps..
Explanation:
'Motile' (or moving) cilia are found in the lungs, respiratory tract and middle ear. ... These cilia have a rhythmic waving or beating motion. They work, for instance, to keep the airways clear of mucus and dirt, allowing us to breathe easily and without irritation.
Answer: to keep airway clear of mucus and dirt allowing us to breathe easy
Explanation:
If Tracy were to put the pizza on the countertop to cool down, which temperature do you predict the pizza would get to?
a. -1 degrees Celsius
b. 10 degree Celsius
c. 27 degree Celsius
d. 93 degree Celsius
e. 260 degree Celsius
Answer:
d. 93 degree Celsius
Explanation:
Plzzzzzzzzzzzzzzzzzzzzzzz mark AS BRAINLIST
All of the following changes to a metal are physical changes except_____.
bending
melting
rusting
polishing
Answer:
D)Polishing..
Answer:
Wouldn't it be rusting
Explanation:
Melting and bending are physical changes so is polishing. so rusting is the only choice, for metal to rust wouldn't it need a chemical change.
__is a term that refers to the amount of space that a substance or an object takes up
how many moles in 1.505x10^23 Na atoms
Answer:
The answer is 0.25 molesExplanation:
To find the number of moles in a substance given it's number of entities we use the formula
[tex]n = \frac{N}{L} \\[/tex]
where n is the number of moles
N is the number of entities
L is the Avogadro's constant which is
6.02 × 10²³ entities
From the question
N = 1.505 × 10²³ Na atoms
We have
[tex]n = \frac{1.505 \times {10}^{23} }{6.02 \times {10}^{23} } = \frac{1}{4} \\ [/tex]
We have the final answer as
0.25 molesHope this helps you
which type of wave shows energy transmitted in a definite direction and with a definite speed?
PLEASE HELP ME!!
I am smaller than Rb and bigger than Na but we are in the same family.
H
K
N
Cs
Is it easier to remove an electron from Mg or from Cl?
Mg
Cl
Answer: K and Mg
Explanation:
The first one refers to the atomic radius and increases going down and to the left on the periodic table. K is in between Rb and Na.
What is the process that occurs when repeated freezing and thawing breaks apart rocks?
Erosion
Deposition
Physical weathering
Chemical weathering
Answer:
C. Physical weathering.
Answer: C. Physical weathering.
Explanation:
16. The diffusion rate of an unknown gas is measured to be 31.50 mL/min. Under
identical conditions, the diffusion rate of oxygen gas is measured to be 30.50
mL/min. Hint: diffusion rate is directly related to velocity.
Determine the identity of the unknown gas from the following options:
a. CH4
b. CO
C. NO
d. CO2
e. NO2
Answer:
Explanation:
[tex]\frac{r_1}{r_2} = \sqrt{\frac{M_2}{M_1} }[/tex]
r₁ and r₂ are rate of diffusion of gas having molecular mass of M₁ and M₂
[tex]\frac{31.5}{30.5} = \sqrt{\frac{32}{M_1} }[/tex]
1.0666 = 32 / M₁
M₁ = 30
molecular weight of NO = 14 + 16 = 30
So the unknown gas is NO .
When iron reacts with oxygen, it forms iron oxide, or rust.
4 Fe + 3 O2 2 Fe2O3
If 112 g of iron (Fe) combines with 24 g of oxygen (O2), how much iron oxide is formed?
Answer:
Mass of iron oxide: 79.85 g
Explanation:
Given data:
Mass of iron = 112 g
Mass of O₂ = 24 g
Mass of iron oxide formed = ?
Solution:
4Fe + 3O₂ → 2Fe₂O₃
Number of moles of Fe:
Number of moles = mass/ molar mass
Number of moles = 112 g/ 55.85 g/mol
Number of moles = 2 mol
Number of moles of O₂:
Number of moles = mass/ molar mass
Number of moles = 24 g/ 32 g/mol
Number of moles = 0.75 mol
Now we will compare the moles of oxygen and iron with iron oxide.
Fe : Fe₂O₃
4 : 2
2 : 2/4×2 = 1
O₂ : Fe₂O₃
3 : 2
0.75 : 2/3×0.75 = 0.5
The number of moles of iron oxide formed by oxygen are less thus it will be limiting reactant.
Mass of iron oxide:
Mass = number of moles × molar mass
Mass = 0.5 mol × 159.69 g/mol
Mass = 79.85 g
Answer:
136 g Fe2O3
Explanation:
study island
In Natural selection, individuals whose unique characteristics are well-suited for an environment tend to survive and produce more offspring. true or false? i need this help!right now!
Answer:
True
Explanation:
True. If an animal has attributes to it that help it survive better in an environment, it will survive better than its counterparts who do not have this attribute. More survival = More offspring
Answer:
True.
Explanation:
It's called survival of the fittest. Animals are genetically supposed to be well suited to their environment and if they aren't, they die out.