Answer:
What are the two animals?
Explanation:
PLEASE HELP!!!!!!!!!!!!!!!!!!!! ASAP!!!!!!!!! Which two elements are mainly found in the inner and outer core?
A. Fe and Ni
B. Fe and Si
C. Ni and Si
D. Ni and C
PLEASE TELL ME WHAT THOSE ABREVIATIONS MEAN ALSO!!!!!!!!!!!!!
Question 5
Which of the following is not an example of mutualism?
How many moles of a gas sample are in a 5.0 L container at 373 K and 203 kPa?
0.33 mole
0.66 mole
1.11 moles
3.05 moles
Answer:0.33
I'm not sure tho
Answer:
0.33
I just took the test.
Graphite has a specific heat of 0.709 J/gºC. If a 25 gram piece of graphite is cooled
by 17°C, how much energy was lost by the graphite?
Answer:
[tex]\boxed {\boxed {\sf 301.325 \ Joules }}[/tex]
Explanation:
Since we are given the mass, specific heat, and change in temperature, we should use this formula for energy:
[tex]q=mc \Delta T[/tex]
The mass of the graphite is 25 grams. Graphite's specific heat is 0.709 J/g °C. The change in temperature is 17 degrees Celsius.
[tex]m= 25 \ g \\c= 0.709 \ J/g \ \textdegree C \\\Delta T= 17 \ \textdegree C[/tex]
Substitute the values into the formula.
[tex]q= (25 \ g)( 0.709 \ J/g \ \textdegree C )( 17 \ \textdegree C)[/tex]
Multiply the first two numbers. The grams will cancel.
[tex]q= 17.725 \ J/ \textdegree C(17 \ \textdegree C)[/tex]
Multiply again. This time the degrees Celsius cancel.
[tex]q= 301.325 \ J[/tex]
The graphite loses 301.325 Joules of energy.
One of the main jobs of _________ is to support the leaves
The flowers
the seeds
the roots
the stem
Answer:
Stem
Explanation:
Answer:
option-(d) stem
Explanation:
Stems have four main functions which are: Support for and the elevation of leaves, flowers and fruits. The stems keep the leaves in the light and provide a place for the plant to keep its flowers and fruits. Transport of fluids between the roots and the shoots in the xylem and phloem...
I hope it help you
A sample of nitrogen gas contains 8.23 x 10^23 molecules. What is the volume of this sample at STP?
Please show and explain the steps.
Answer:
30.6 L
Explanation:
Given data:
Number of molecules of nitrogen = 8.23×10²³ molecules
Volume occupy at STP = ?
Solution:
Standard temperature = 273.15 K
Standard pressure = 1 atm
One mole of any substance at STP occupy 22.4 L volume.
Number of moles of nitrogen:
1 mole contain 6.022×10²³ molecules.
8.23×10²³ molecules × 1mol / 6.022×10²³ molecules
1.37 mol
Volume of nitrogen:
1.37 mol × 22.4 L / 1 mol
30.6 L
1.
What is the light that you can see called?
VED
DANCE
WOW
EN
M
W
NOGO
OLET
a) observatory light
c) visible light
b) ultraviolet light
d) infrared light
Answer:
The correct answer is c. Your welcome
PLEASE HELP Will give brainliest and 50 points!! Please give honest answers
Answer this chemistry question below
At certain times of year , the oceans get warmer. Which part of the water cycle is directly affected by the warming of the ocean water?
Review the poster.
https://www.cdc.gov/handwashing/pdf/wash-your-hands-fact-sheet-508.pdf
What is the greatest advantage of using a poster to present the information in “Stop Germs! Wash Your Hands”?
A poster that features brief sentences conveys urgency and simplifies content.
The extensive detail in posters captures viewers and causes them to stop and read.
The colors and images of a poster often convey a stronger message than words.
A poster appeals to several senses at once, which makes it hard to ignore.
A. A poster that features brief sentences conveys urgency and simplifies content.
plsss help ASAP!!!
BRAINLIEST
Answer:
-175.15
Explanation:
1.0 °C = 274.15 K
2.0 °C = 275.15 K
3.0 °C = 276.15 K
4.0 °C = 277.15 K
5.0 °C = 278.15 K
6.0 °C = 279.15 K
7.0 °C = 280.15 K
8.0 °C = 281.15 K
9.0 °C = 282.15 K
What is the control center or “brain” of a cell called?
Answer: The nucleus is often referred to as the control center, or brain, of the cell and contains the DNA, or genetic material. The nucleus is surrounded by the nuclear envelope. ... Human cells are eukaryotic cells.
Explanation:
Answer:
Nucleus
Explanation:
not to good at explaining but I'm hoping this is right!
Need help plz!
-Which property describes a mixture?-
A. It cannot be separated by physical methods.
B. It has a single chemical composition.
C. It cannot have more than one state of matter.
D. It cannot be described by a chemical symbol or formula.
Answer:
D as a mixture is not a compound and it does not have it's own chemical formula
Explanation: Sauce me brainliest
It cannot be described by a chemical symbol or formula.
- Chilio
A regional metamorphic belt is divided into zones based upon
Please help me :D I’m begging rn lol
Answer:
To catch a ball, the fielder has to stop the ball. This means, force is applied against the motion of the ball. So, between the fielder applies force on the ball and the ball comes to rest, the ball moves in the direction opposite to the direction of force. Thus work is negative.
Explanation:
MARK ME AS BRAINLIEST PLSSS
You have 50 g of radioactive C-14. The half-life of C-14 is 5,730 years. How many grams would you have left after 5,730 years?
Why did Mendeleyev try to reorganize the periodic table?
Is NO ionic or covalent
1.State the relationship between the following properties:
a) mass and number of moles__________
b) number of moles and number of particles __________
6. Show how you will compute for the number of particles given the following:
a) Mass of the sample__________
b) Number of moles of the sample__________
Thankyouu po sana my mag answer
Answer:
bytbyufvguv vvg uggy yvgu vgu gyu7yng8ugng88yn
Help thanks thanks thanks
Answer:
the answer is (G)
Explanation:
It is G!
Your welcome!
Give an example of an object that has potential energy
Answer:
A book on a shelf
Explanation:
what kind of substance is rust
find the product of (x+a)(x-a)
Answer:
x^2 - a^2
Explanation:
What is the mass of 0.55 mole
of magnesium chloride?
Answer:
SYMBOLS, FORMULAS AND MOLAR MASSES
OBJECTIVES
1. To correctly write and interpret chemical formulas
2. To calculate molecular weights from chemical formulas
3. To calculate moles from grams using chemical formulas
INTRODUCTION
Part I. Symbols and formulas
An element is a homogeneous pure substance made up of identical atoms. All matter is made
up of elements and, since chemistry is the study of matter, it is convenient to use symbols to represent
the elements rather than using the entire name.
By international agreement, specific symbols are assigned to each element (Note: This means
that while names of the elements vary with language, symbols are constant throughout the world.) Each
element is assigned a one- or two-letter symbol. The first letter is capitalized, the second (if there is
one) is not. While this often seems trivial, it is in fact a very important point. For example, in chemical
language Co represents cobalt, which is a metal and an element, while CO represents carbon monoxide,
a compound which is a colorless, odorless gas! Even when there is not an obvious correspondence,
for instance "MN", it can cause confusion. Do you mean the element manganese? Did you forget a
letter and mean something else? Are you using "M" to represent something else entirely? Chemists
sometimes use "M" to represent any metal. It is well worth the trouble to memorize the symbols for
common elements.
Since compounds consist of elements, the chemical formulas of compounds also consist of
elements with subscripts used to denote the number of atoms per molecule. If there is no subscript, it is
implied that there is one of that kind of atom. Ones never appear in chemical formulas. Not only do
subscripts denote ratios of atoms, they also denote the ratio of moles of element to one mole of
compound. Parentheses can be used to show groups of atoms, with the subscripts showing how many
groups there are. Parentheses are not used if there is only one group.
Examples: For one mole of the following compounds, how many moles of each element are
present?
MgCl2 1 mole Mg, 2 moles Cl
Mg(NO3)2 1 mole Mg, 2 moles N, 6 moles O
NaNO3 1 mole Na, 1 mole N, 3 mole O
AgCl 1 mole Ag, 1 mole ClPart II. Molar Masses
Each atom has a different size and therefore a different mass. The relative masses of each
element can be found on the periodic table. For example, one atom of magnesium weighs 24.31 amu
(atomic mass units). However, one mole of magnesium weighs 24.31 g. (Moles were planned that
way!) Since one mole of MgCl2 consists of one mole of magnesium and two moles of chlorine, the
mass of one mole of MgCl2 must be the sum of the masses of the elements. The mass of one mole of a
substance is called the molar mass or molecular weight.
Examples: What is the molar mass of the following compounds?
MgCl2 24.31 + 2(35.45) = 95.21 g/mol
Mg(NO3)2 24.31 + 2(14.01) + 6(16.00) = 148.33 g/mol
NaNO3 23.00 + 14.01 + 3(16.00) = 85.01 g/mol
AgCl 107.9 + 35.45 = 143.4 g/mol
(Note: Yes! You DO have to count significant figures when calculating molecular weight/molar
mass. However, the number of significant figures may vary depending on which periodic table you use.)
Chemists are generally interested in number of moles. Unfortunately, it is impossible to measure
moles directly. However, masses are easily measured, and if the chemical formula of the compound is
known, the molar mass can be used to determine the number of moles. The molar mass is defined as:
molar mass = grams/moles = g/mol (1)
Moles may be calculated by using molar mass as a conversion factor in dimensional analysis where
molar mass in grams = 1 (exactly) mole of compound (2)
This method is used in multi-step calculations. For example, if 0.873 g of MgCl2 is weighed out, it
is 9.17 x 10-3
moles.
1 mole
0.873g x 95.21 g = 9.17 x 10-3
mol MgCl2 (3)
However, 0.873 g of AgCl is only 6.09 x 10-3
mol.
1 mole
0.873g x 143.4 g = 6.09 x 10-3
mol AgCl (4)Molar mass may also be used to relate moles to grams. For example, 0.158 mol of MgCl2 is 15.2 g.
0.158 mol x 95.21 g = 15.2 g MgCl2 (5)
1 mol
Percent is used to express parts per one hundred. Usually in chemistry, it refers to
g of species of interest x 100 = % (6)
g of whole thing
Example: For the % Mg in MgCl2: In one mole of MgCl2, there are 24.31 g of Mg (molar mass of Mg,
the part we are interested in) and 95.21 g of MgCl2 (the whole thing), so %Mg in MgCl2 is
(24.31/95.21) x 100 = 25.53% Mg (7)
PROCEDURE
Work individually.
The formula for calcium phosphate is Ca3(PO4)2. Weigh about 2 g of calcium phosphate to the
nearest 0.001 g. In other words, you do not have to have exactly 2.000g, but you must know the
weight you have exactly. Acceptable results include but are not limited to: 1.985g , 2.035g, 2.314g
etc.
Be sure to report all results with the correct number of significant figures and appropriate units!
lons form when atoms gain or lose valence electrons. When an atom gains
electrons, it becomes negatively charged, and when an atom loses
electrons it becomes positively charged. Why?
Answer:
In neutral atom number of electrons (negativity charged particle) and number of proton ( positively charged particle) are equal.
When one or more electrons are lost so positive charge particle increases and cation is formed.
For example in Na 11 electrons and 11 protons are present when it loses one electrons protons are 11 and 10 electron are remaining so one positive charge is present.
Morever when an element gain electrons one negative charge increases and anion is formed. For example in Cl 17 proton and 17 electrons are present when it gain one electron 18 electrons and 17 protons are now present one negative is more so anion negative ion is formed.
Explanation:
is A bond a chemical attraction between two atoms?
Answer:
Yes, a chemical bond is a lasting attraction between two atoms. (I am not completely sure what you mean, but I hope this helps!)
Do liquids have kinetic energy? Yes or no.
Answer:
YESSIR
Explanation:
Why don't we feel the air pressing on us all the time?
Answer: Why don't we feel the air pressing on us all the time?
Explanation:
Because air is a fluid, the weight of the air is transmitted to the palm of your hand and to the back of your hand at the same time. These forces cancel so that your hand overall feels no net force
Answer:the gravity in the atmosphere is pulling all the air so we can survive
Explanation:
how many molecules are in 4 moles of He?
Answer:
⇒ n = 2.4088 × 10²⁴
- So, the no of atoms in 4 moles of helium is 2.4088 × 10²⁴.
Explanation: