Answer:
Srry its so hard
Explanation:
When was Quartz found and how is it extracted??
Answer:
Quartz was discovered in 1880 and they use buldozers and backhoes (to remove dust/dirt around it) and rarely explosives.
Explanation:
Fill in the blanks with the correct words.
The movement of molecules from an area of low concentration to an area of high concentration occurs in help plz in being timed I’ll mark u Brainlyest
transport.
transport, molecules move from an area of high concentration to an area of low concentration.
In
Intro
Done
Answer:
i had this same question and the answer is electron.
Explanation:
How many atoms are present in a sample of Calcium (Ca) weighing 127.38g?
Answer:
1.9139 × 10²⁴ atoms Ca
General Formulas and Concepts:
Chemistry - Atomic Structure
Reading a Periodic TableUsing Dimensional AnalysisAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Explanation:
Step 1: Define
127.38 g Ca
Step 2: Identify Conversions
Avogadro's Number
Molar Mass of Ca - 40.08 g/mol
Step 3: Convert
[tex]127.38 \ g \ Ca(\frac{1 \ mol \ Ca}{40.08 \ g \ Ca} )(\frac{6.022 \cdot 10^{23} atoms \ Ca}{1 \ mol \ Ca} )[/tex] = 1.91388 × 10²⁴ atoms Ca
Step 4: Check
We are given 5 sig figs. Follow sig fig rules and round.
1.91388 × 10²⁴ atoms Ca ≈ 1.9139 × 10²⁴ atoms Ca
at what distance above the surface of the Earth is the acceleration due to Earth gravity 0.95 metre per second
square
To Find :
At what distance above the surface of the Earth is the acceleration due to Earth gravity 0.95 meter per second square.
Solution :
Let, acceleration due to gravity at height h is [tex]g_h[/tex].
[tex]\dfrac{g_h}{g}=\dfrac{R^2}{(R+h)^2}\\\\\dfrac{(R+h)}{R}=\sqrt{\dfrac{9.8}{0.95}}\\\\\dfrac{(R+h)}{R}=3.2\\\\h = 3.2R - R\\\\h = 2.2R\\\\h = 2.2\times 6400 \ km \\\\h = 14080\ km[/tex]
Therefore, the height is 14080 km.
Hence, this is the required solution.
How much heat is required to raise the temperature of a 6.21 g sample of iron from 25.0 oC to 79.8 oC?
Answer:
151.1J
Explanation:
Given parameters:
Mass of iron = 6.21g
Initial temperature of iron = 25°C
Final temperature of iron = 79.8°C
Unknown:
Amount of heat = ?
Solution:
The amount of heat require to cause this temperature can be determined using the expression below;
H = m c (T₂ - T₁)
H is the amount of heat
m is the mass
c is the specific heat capacity
T is the temperature
Specific heat capacity of iron 0.444J/g°C
Insert the parameters and solve;
H = 6.21 x 0.444 x (79.8 - 25)
H = 151.1J
Is nitrogen reactive or stable?
A reactive
B stable
Nitrogen is reactive I think
Beth has two unlabeled balloons, one filled with hydrogen gas and the second filled with neon gas. She researches and writes down the density of hydrogen and neon. Beth also has several chambers filled with various gases and a poster showing the densities of these gases. She has no other materials or tools available to her to help her identify the element in each balloon. The poster and Beth’s data are shown. Select the gas from the poster that Beth should use in an experiment to identify the element in each balloon. Explain your answer.
Answer:
Aargon is NOT the answer.
Explanation:
Sounds with small amount of energy______distances than sounds with more energy
A.Shorter
B. Longer
C.same
D. Medium
Consider the reaction: 3 N2 (g) + 2 O3 (g) → 6 NO (g) ΔfH ° (kJ/mol) 0.00 142.26 90.37 Sm ° (J mol-1 K-1) 191.5 237.7 210.6 What is ΔrG ° for this reaction in kJ/mol at 350 K?
Answer:
Explanation:
3 N₂ (g) + 2 O₃ (g) → 6 NO (g)
Δ H(rxn ) = 90.37x 6 - ( 0 + 142.26 x 2 )
= 542.22 - 284.52
= 257.7 kJ
Δ S(rxn ) = 6 x 210.6 - ( 2 x 237.7 + 3 x 191.5 )
= 1263.6 - ( 475.4 + 574.5 )
= 213.7 J / K
Δ G = Δ H - T Δ S
= 257.7 - 350 x 213.7
= - 74537.3 kJ .
Δ G / mole = - 74537.3 / 6 = - 12422.88 kJ / mol.
Which pair of elements can form ionic bonds?
A.
copper (Cu) and nitrogen (N)
B.
gallium (Ga) and phosphorus (P)
C.
hydrogen (H) and sulfur (S)
D.
phosphorus (P) and fluorine (F)
E.
potassium (K) and bromine (Br)
Answer:
E. potassium (K) and bromine (Br)
Explanation:
An ionic bond is formed between compounds with a large electronegativity difference between them. It is usually between a metal and non-metal.
Potassium is a true metal found in group 1 on the periodic table. Bromine is a highly electronegative non-metal which is a halogen. Potassium will lose one of its electrons which will be gained by the Bromine. The electrostatic attraction between the two species will cause the ionic bond to form. The ability of one specie willing to lose electron and the other gaining, is the main bed rock of ionic bonding.Answer:
Correct answer: E. potassium (K) and bromine (Br)
Explanation:
(Correct answer for (portal and Edmentum users too)
Hope I was helpful :) good luck on your school work and have a great day
Write the group number using both A/B and 1-18 notation for elements that have the
following outer electron configuration:
a 252
b. 3523p3
c. 4s23
d. 5524d105p4
Which statement best describes what the volume of an object represents
Answer:
Volume is the amount of space taken up an object.
Among the following, which is NOT an ionic compound?
Ca3N2
N204
AICI:
NaCl
Answer:
NaCl
Explanation:
HCI is a poiar covalent compound while ℂI4 is a non-polar covalent compound because both are iormed by sharing of electrons. KCl and NaCl are formed by the transfer of electrons and are ionic compounds.
Two students made the Lewis dot diagrams of NH3. The diagrams are as shown. Two visual diagrams of an N H three molecule are shown. Student As diagram on the left has nitrogen at the center and connects with each hydrogen atom by an arrow pointing away from the nitrogen, one below, one on the right, and one on the left. There is a pair of dots above the nitrogen atom. Student Bs diagram on the right has nitrogen at the center connecting by a straight line to each hydrogen positioned below, to the left, and to the right of nitrogen. There is a pair of dots above the nitrogen atom. Which student drew the correct Lewis dot diagram? Only Student A Only Student B Both Student A and Student B Neither Student A nor Student B
Answer:
Only Student A
Explanation:
The first thing to consider in the diagrams of student A and B is to be sure that that the diagrams obey the octet rule and represent the written formula of ammonia (NH3). Clearly, only the diagram drawn by student A satisfy the these conditions.
If we look at the both diagrams closely, we will discover that the diagram drawn by student B does not satisfy the octet rule nor the trivalency of nitrogen even though it shows the lone pair of electrons on nitrogen hence it can not be the correct dot electron structure for NH3.
Answer: It is neither A or B
Explanation: I took the test and got this correct. Many people are saying only B, but that is wrong.
( please give brainliest :) )
8. Chuck wants to investigate how gas molecules move in a container. Which model would be helpful to represent this motion?
A.) stacking blocks to build a tower
B.) freezing water in a ice cube tray
C.) bouncing elastic balls off of each other and the walls of a room
D.) placing a closed, water-filled plastic bag in the sun and watching condensation form
Answer:
nuts in yo mouth
Explanation:
Answer:
I'm not 100% sure but it's not A or B. It's probably cc
Explanation:
tell me about yourself
Answer:
Tell picture above is a sample of tell me about yourself
How much heat energy is needed to raise the temperature of 135 g of water (specific heat of water = 4.19 J/g-C) from 15 degrees Celsius to 27 degrees Celsius?
Answer:
Required heat = 6,787.8 j (Approx)
Explanation:
Given:
Mass of water = 135 g = 0.135 g
Specific heat of water = 4.19 J/g-C
Change in temperature = 27 - 15 = 12 degrees Celsius
Find:
Required heat
Computation:
Required heat = mcΔt
Required heat = (135)(4.19)(12)
Required heat = 6,787.8 j (Approx)
What would happen if a researcher failed to realize a thermometer he or she was using has a Celsius and Fahrenheit scale?
Answer:
To obtain a more accurate read on temperature, the researcher should make sure to measure temperature by Celsius degrees rather than Fahrenheit.
Explanation:
Temperature is a measure of heat intensity. In food science experiments, you should always require an exact description of heat intensity. The most commonly used unit of temperature in the laboratory is the Celsius degree because the Celsius temperature scale is based on the boiling and freezing points of pure water. The difference between the points of boiling and freezing temperatures (at 1 atmosphere of air pressure) is divided into 100 equal units, making a Celsius degree 0.01 of the difference between the boiling and freezing points of water, making it the most accurate method of exact temperature reading. It is important to use the Celsius scale if you have a thermometer that reads Celsius and Fahrenheit.
A scientist observes rock masses that have moved past each other in opposite horizontal directions. Which feature does the scientist observe?
Answer: strike-slip fault
Explanation:
Answer:
C; strike split
Explanation:
1. Matter is described by its properties which are:
a. the characteristics of a substance that make it similar to others
b. the characteristics of a substance that make it unique
c. the amount of houses it owns
d. anything that takes up space
2. Physical properties that we use to describe matter are:
a. mass, weight, volume and density
b. color, mass, weight, and density
c. density, mass, size and smell
d. mass, scale, volume and density
3. Mass is how _______ is in an object
a. much matter
b. much weight
c. much atoms
d. all of the above
4. The mass of an object remains constant, but its weight may change depending on:
a. the number atoms
b. the volume
c. the density
d. gravitational pull
5. Density can be described as:
a. the number atoms in an objects mass
b. the volume of an object plus its mass
c. the amount of mass in a given volume
d. something similar to weight
you dont have to answer them all. whatever you can do is fine
Answer:
3=a 5=b 4=d 2= b yea that's pretty much the answers
A very hot cube of copper metal (32.5 g) is submerged into 105.3 g of water at 15.4 0C and it reach a thermal equilibrium of 17.3 0 Calculate the initial temperature of copper (Cs = 0.385 J/g 0C for copper, and 4.18 J/g 0C for water).
Answer:
The initial temperature of the metal is 84.149 °C.
Explanation:
The heat lost by the metal will be equivalent to the heat gain by the water.
- (msΔT)metal = (msΔT)water
-32.5 grams × 0.365 J/g°C × ΔT = 105.3 grams × 4.18 J/g °C × (17.3 -15.4)°C
-ΔT = 836.29/12.51 °C
-ΔT = 66.89 °C
-(T final - T initial) = 66.89 °C
T initial = 66.89 °C + T final
T initial = 66.89 °C + 17.3 °C
T initial = 84.149 °C.
Correct the following statements
a.an element is a combination of two or more compounds
b. When a small amount of sugar is completely dissolved in water, a heterogeneous solution is formed
Answer:
a. Any substance that contains only one kind of an atom is known as an element. Because atoms cannot be created or destroyed in a chemical reaction
b. Sugarsolution is a homogeneous mixture because any substance dissolved in water becomes a homogeneous mixture
Identify a metalloid from the following
(1) Antimony
(2) Sodium
(3) Aluminium
(4) Helium
Antimony
Hope it helps
Answer:
[tex]\boxed {\boxed {\sf 1. \ Antimony}}[/tex]
Explanation:
A metalloid is an element that is "in between" a metal and non-metal. They display some properties of both.
On the Periodic Table, the metalloids are found in a zig-zag step pattern to the right of the metals and the left of the non-metals.
There are 7 metalloids: boron, silicon, germanium, arsenic, antimony, tellurium, and polonium.
So, the correct answer is 1. Antimony
How can air quality be fine on one day and hazardous on the next? What
are some things that can cause a rapid change in air quality? *
Answer:
Air Current
Explanation:
Say I am in California and there is a massive fire next to me but not close enough to me to really see the fire and the next day I see no fire but theres a ton of ash in the sky, this can be due to the wind current taking the smoke from the fire into my direction and that smoke falling in my area. So basically a wind current can take the smoke from a fire into another destination and cause a rapid change in air quality in a day.
List 4 important uses of Quartz
Answer:
Transparent Rock Crystal has many electronic uses; it is used as oscillators in radios, watches, and pressure gauges, and in the study of optics. Quartz is also used as an abrasive for sandblasting, grinding glass, and cutting soft stones.
Explanation:
what is the name of this atom?
A.) Beryllium
B.) Boron
C.) Fluorine
D.) Helium
Answer:
Explanation:
A .
K20
Molar Mass (g/mole)
2(39.10) + 16.00 = 94.20 g/mole
Moles
5.85 moles
Mass (grams)
Particles
Answer:
yes
Explanation:
that is the answer
When an element in the first group of the periodic table
reacts with an element in the seventh group, what is the
type q bond that is likely to be formed?
Answer:
An ionic bond
Explanation:
They are most likely going to form an ionic bond.
An ionic bond is where atoms lose/gain electrons.
It is easier for elements in the first group to lose the one electron on their valence shell and for elements in the second group to take that.
Some examples are Sodium Chloride (NaCl) and Potassium Chloride (KCl)
Explain how a substances flammability can indicate a chemical change.
Answer:
This is simple, if it has a high flammability, and you light it on fire, then that would be a chemical change.
Explanation:
May I have brainliest please? :)
Which of the following correctly describes the electrical charges of subatomic particles?
B Protons/positive; neutrons/negative; electrons/negative
C Protons/neutral; neutrons/positive ; electrons/negative
D Protons/negative; neutrons/neutral; electrons/negative
Answer:
D Protons/negative; neutrons/neutral; electrons/negative
Explanation:
There are three fundamental subatomic particles found in atom which are the protons, neutrons and electrons.
Protons are the positively charged particlesNeutrons are neutral and do not carry any chargesElectrons are negatively charged.In the tiny central nucleus, both protons and neutrons can be found
The electrons occupy the bulk volume of the atom.