Answer:
Elements and compounds are two types of pure substances.
Explanation:
USE LETTERS FOR ANSWERS, NO NEED TO EXPLAIN
a) Substitute symbols and formulas for words.
b) Predict the products. If no reaction occurs, write “NR” after the --> sign. c) Include abbreviations for the physical state.
d) Write out and balance the equation.
6. Mercury is poured into an aqueous solution of zinc nitrate.
7. Solutions of potassium iodide and lead (II) nitrate are mixed. The resulting lead compound is a precipitate.
thank you! :)
Answer:
Ok:
Explanation:
6a) [tex]Hg + Zn(NO_3)_2\\[/tex]
b) NR
c) [tex]Hg_{(l)} + Zn(NO_3)_2 {(aq)}=> NR[/tex]
d) Welp, no reaction so i don't know.
7a) [tex]KI + Pb(NO_3)_2[/tex]
b) [tex]PbI_2 + KNO_3[/tex]
c) All are aqeuous except for PbI2 which is solid
d) [tex]2KI _{(aq)}+ Pb(NO_3)_2_{(aq)} => PbI_2_{(s)} + 2KNO_3_{(aq)}[/tex]
Check if that is ok or if my work has any issues :).
List the 3 particles of an atom (w/their symbol & charge)
Proton p +1
Neutron n 0
Electron e- -1
2C3H7OH + 9O2 --> 6CO2 + 8H2O
Determine the number of grams of CO2 produced from the reaction of 5.55 moles of C3H7OH?
a
1466 g
b
16.7 g
c
367 g
d
12.2 g
e
733 g
Please show work
Answer 12.2g is the answer
a sample of an unknown metal has a mass of 21.6g and volume of an 8.00cm3 calculate the density of the unknown metal
Answer:
2.70 g/cm³Explanation:
The density of a substance can be found by using the formula
[tex]density = \frac{mass}{volume} \\[/tex]
From the question we have
[tex]density = \frac{21.6}{8} \\ = 2.7[/tex]
We have the final answer as
2.70 g/cm³Hope this helps you
when 45mL of 0.25mol/L sulfuric acid is mixed w/ 25mL of 0.58mol/L Calcium hydroxide, the solution has a?
3. How many moles of H20 are in 15.2 grams of pure ice?
Answer:
18.01528 grams.
Explanation:
Ther are 0.84 moles of [tex]H_{2}O[/tex] in 15.2 g of pure ice.
The molar mass of [tex]H_{2}O[/tex] is 18g.
To calculate the number of moles of a substance in a given mass of the sample, we divide the given mass by the molar mass of the sample,
Number of moles = given mass / molar mass
It is given that we have 15.2g of pure ice. Then the number of moles of [tex]H_{2}O[/tex] will be:
n = 15.2/18
n = 0.84 moles.
Learn more about molar mass:
https://brainly.com/question/1855861
Why do molecules change the speed? (SELECT ONE)
Claim 1: Molecules speed up when energy is created and slow down when energy is destroyed.
Claim 2: Molecules speed up when they get energy from other molecules and slow down when they give energy to other molecules.
Answer:
Molecules speed up when they get energy from other molecules and slow down when they give energy to other molecules.
Explanation:
We know from the first law of thermodynamics that energy can not be created nor destroyed.
However, according to the kinetic molecular theory, molecules collide frequently with each other. All molecules in a substance do not possess equal energy hence some molecules are more energetic than others.
When a more energetic molecule collides with a less energetic molecule, the more energetic molecule transfers energy to the less energetic molecule. The less energetic molecule speeds up while the molecule that collided with it slows down due to energy transfer from one molecule to another.
What part does chlorophyll play in photosynthesis?
A. It transports sugar and water to plant leaves
B. It uses suns energy to “cook”water and carbon dioxide
C. It drinks water from the soil around the roots of the plant
D. Breathes the air around the plants and gets carbon dioxide
Answer:
B
Explanation:
it uses the process of the light reaction stage and Calvin cycle to trap sunlight in the day and make food at night
Answer:
I think the answer is A or B
Please help
mg(oh)2
How many H atoms are there?
How many Mg?
What is the total number of atoms?
Answer:
There are 2 hydrogen atoms, one magnesium atom, and 5 atoms in total.
Explanation:
We are given a compound in formula form. To make things easier to understand, we can first convert this to the name of the compound.
When a compound contains one or more elements in parentheses, these are usually a polyatomic ion. Polyatomic ions are ions made up of two or more elements with a positive or negative charge over the entire ion. Commons examples of these NH₄⁺ (ammonia) and HCO₃⁻ (bicarbonate). You can combine metals with polyatomic ions to create commonly known compounds, such as baking soda. The chemical name for baking soda is sodium bicarbonate, so we can combine Na (sodium) with HCO₃⁻ (bicarbonate) and create sodium bicarbonate: NaHCO₃.This compound is one magnesium atom bonded to two hydroxide ions.
Hydroxide is the compound between one hydrogen atom and one oxygen atom. The compound overall adopts a negative charge of 1.If we have one hydrogen atom and one oxygen atom, the most electronegative atom is written first in chemical formulas. Therefore, the symbol for Oxygen (O) goes first.Then, write in the hydrogen atom directly after the O symbol: OH.Finally, since we have a negative charge on the ion, we need to play a negative sign as a superscript for the compound. Therefore, this becomes OH⁻.Now, we need to determine the charge on the Magnesium atom which is determined from the amount of valence electrons the atom has.
On a periodic table, the symbol for Magnesium is Mg and this element has 2 valence electrons. In order to fulfill the Octet Rule, the It is more likely to give up 2 electrons to a nonmetal than it is to gain 6, so we can safely assume that the charge is ²⁺.We need to use the criss-cross technique to transfer the charges between the element and the ion, so the negative 1 charge goes to the Mg, which does not appear (negative 1 or positive 1 are implied) and since the magnesium has a charge of positive 2, this is the subscript for the hydroxide ion.Therefore, our compound becomes Mg(OH)₂, and we have labeled this as magnesium hydroxide.Now, to the number of atoms:
The new charge on Mg is 1-, so there is only one atom of Mg.The charge is 2+ on the OH ion, so there are two atoms of H and two atoms of O.Two atoms of oxygen, two atoms of hydrogen, and one atom of magnesium add up to be five atoms in total.scientific notation, fill in the blank.
7.95x10^7 = [ ? ]x 10^6
Answer:
79.5
Explanation:
7.95x10^7 IS 79500000.
If you bring the decimal point left 6 more times it would be 79.500000
which rock is the result of changes on the Earth's surface?
igneous rock
sedimentary rock
metamorphic rock
Answer:
metamorphic
Explanation:
when one rock changes another rock the rock that got changed is now metamorphic
Which best explains why the atomic theory is a scientific one?
A. The theory was written by a famous scientist and has been around
for a very long time.
B. The theory describes what atoms are and has not changed over
time.
C. The theory explains many observations and is supported by a
large amount of evidence.
D. The theory represents a guess by many different scientists about
how atoms work.
Answer:
C
Explanation:
Answer:
it will option c it is perfect
3. When substances cross cell membranes by simple diffusion, they
a. squeeze between phospholipid molecules.
b. have help from channel proteins.
C. move from a higher to lower concentration.
d. two of the above
Answer:B
Explanation:due to osmosis and osmoregulation of the cell membrane
HELP!!! ASAP!!!! WILL MARK BRAINLIEST!!!!
A certain covalent compound contains sulfur bonded to chlorine. Which of the following statements about this compound is correct?
Question 5 options:
A)
Electrons will reside closer to sulfur, and the bond will be non-polar.
B)
Electrons will reside closer to sulfur, and the bond will be polar.
C)
Electrons will reside closer to chlorine, and the bond will be polar.
D)
Electrons will reside closer to chlorine, and the bond will be non-polar.
Answer:
C) Electrons will reside closer to chlorine, and the bond will be polar
Explanation:
Electrons tend to be closer or attracted to high electronegativity and sulfur has less electronegativity than chlorine. Therefore, electrons will reside closer to chlorine. To find out if it is polar or nonpolar, according to the electronegativity chart you can find online, you can see that the electronegativity of sulfur is 2.5 while the electronegativity of chlorine is 3.0. Because the difference between these two is a slight change, it would be slightly polar. So, the bond will be polar.
Answer:
Electrons will reside closer to chlorine, and the bond will be polar.
Explanation:
Please help!! This would mean so much to me!!
Answer:
I think it's the A one. Hope it's correct
Answer:
A option is correct
Explanation:
For many plants, carbon dioxide is a limiting factor.
What happens when more carbon dioxide is available to plants?
1.Plant growth increases.
2.Plant growth stays the same.
3.Plant growth decreases.
4.Plant growth may increase or decrease.
Answer:
1
Explanation:
plants use carbon dioxide and if there is more then that mean the plants will have more to use and will grow faster and populate more
In the morning, Rafael notices that the Sun appears on one side of the sky. In the evening, he notices that the Sun appears to be on the other side of the sky. However, in class, Rafael learned that the Sun does not actually move across the sky from one side to another.
Why does it appear that the Sun starts the day on one side of the sky and ends the day on the other?
A.
The Sun spins.
B.
The Earth has two Suns.
C.
The Sun moves around the Earth.
D.
The Earth spins.
Answer: The earth spins while we also rotate around the sun the sun is well to us still when actually in reality the whole galaxy is moving but our planet spins and with it comes to night and day.
Explanation:
What is the conversion for 5 g + 3.3 mL =
Answer:
9 g/ml
Explanation:
5 + 3.3 = 8.5
But you should use sig figs.
5 has no tenths, hundredths, and etc.
Therefore the 8.5 rounds up to 9
So the answer is 9.
If the length, width, and height of a box are 9.50 cm, 6.75 cm and 3.50 cm, respectively, what is the volume of the box in units of milliliters and liters?
(a) How many mL will the box contain?
(b) How many L will the box contain?
Answer: 1cm³= 1mL
Explanation:
teachers instructions - “ clear my examples and replace with your own words “ you get brainliest if I get good grade :)
Answer:
can you give me more clearence on what is going on
Explanation:
Density can be calculated by dividing an object's mass by its volume. If the mass of an object is 10 grams and its volume is 2 milliliters, what is its density?
Explanation:
mass =10g. volume=2ml. density=mass/volume = 10/2=5kg/m^3Answer:
5 g/mL
Explanation:
So, if the mass is 10 g and the volume is 2 mL, the density equals...
10 g ÷ 2 mL = 5 g/mL
(sand) and (Sand with water) both of them are heterogeneous
mixture isn't it?
Answer:
yes true
Explanation:
both are heterogeneous
At about what temperature does the sample change phase? Justify your
answer based on the cooling curve shown above.
A student states, “When the alcohol sample was at a temperature of 500 K, all the particles were moving faster than any of the particles were moving at
400 K" Do you agree or disagree with this student's statement? Justify your
answer.
HELP PLZZZZZZZZZZZZZ I WILL GIVE BRAINLIST!!!!!!!!!!!
If you place Alka -Seltzer tablets in a closed container of water, the tablets effervescence then produce a gas. What will eventually happen inside this closed container?
A. Not enough information to determine.
B. The pressure decreases.
C. The pressure increases.
D. The pressure remains the same.
Answer:
c the pressure increases
Emilio wants to tell a friend where an element's name is located within it's box in the periodic table. Which of the following is an accurate explanation to find an element's name?
the name is at the top of the box
the name is the large letter or letter combination in the box
the name is the word below the large letter combination in the box
the name is the last piece of information in the box
Answer:
A
Explanation:
hope this helps!
The name is the word below the large letter combination in the box
ehat is the name of the hydrate Ba(OH)2 8 H2O
Answer: Barium hydroxide octahydrate
Explanation:
To Identify a mineral, there are tests that are used including:
Geologists use the following tests to distinguish minerals and the rocks they make: hardness, color, streak, luster, cleavage and chemical reaction.
2. The atomic number of an atom comes from *
The number of electrons.
The number of neutrons.
The number of protons.
Its atomic mass.
2.1 x 10^-3 x 2 x 10^2 =
a)
4.2 x 10^-5
b)
4.2 x 10^-1
c)
4.2 x 10^1
d)
4.2 x 10^-6
Answer:
I believe it is B
Explanation:
hope it helps. please let me know if it's wrong
Which of the following elements has the strongest attraction for the electrons in a bond?
(A.) hydrogen
(B.) lithium
(C.) bromine
(D.) astatine
Answer:
A)
Explanation:
Entre todos esas materias el hidrógeno es el más fuerte