Answer:
C. A one (1) is assumed when there is no coefficient
Explanation:
The following chemical equation is given in the attachment:
2H2 + O2 → 2H2O
In this reaction, Hydrogen (H2) and oxygen (O2) gases are the reactants and they combine to form H2O, which is the product. It is necessary that, in accordance to the law of conservation of matter, the same number of atoms of each elements on the reactant side equates that on the product side. When this happens, the equation is said to be BALANCED.
However, to balance an equation, COEFFICIENTS are used. In this equation above, coefficients 2 is used in front of both H2 and H2O but no coefficient is used in front of O2. This is because 1 mole of oxygen is on the reactant and product side respectively. However, one is assumed when no coefficient is written i.e. O2 means 1 mole of oxygen molecule.
A cup of coffee is made in the morning by pouring water ov er ground up coffee beans in a piece of paper and by collecting the brown liquid that comes through. Which techniques used
Answer: Filtration technique
Explanation:
The technique used here is called filtration.
Filtration,is a physical separation process that separates a mixture of an insoluble solid from a liquid ( acting as the solvent) by the use of a filter barrier that allows only the fluid to pass through.
In the case from the question,
As water is poured over the ground coffee, it forms a mixture of which the insoluble solid is the coffee grounds, the water is the liquid and the filter barrier is the piece of paper which allows only the brown liquid coffee to pass through as the filtrate.
anyone know this? i’m having trouble...please help.
Help! Will give will give brainllest
1. An airplane flies 1431 miles in 2 hours 15 minutes. What is its average speed in miles per hour?
2. A train travels 76 miles in 1 7/12 hours. What is its average speed in miles per hour?
3. An airplane flies 1914 miles in 2 3/4 hours. What is its average speed in miles per hour?
4. A train travels 102 miles in 2 5/6 hours. What is its average speed in miles per hour?
5. Tracy runs 26.2 miles in 3 hours and 45 minutes. What is her average pace in minutes and seconds?
Answer:
1. 636miles/hour
2. 53.65milesper hour
3.696miles per hour
4.37.09mikes per hour
5. 6.99miles/hour
Explanation:
you first convert all the time into improper fractions
then work out speed which is got by dividing distance with time
a = 10 m/s - 5 m/s
5S
Answer:
what is the formula?
Explanation:
Calculate the molarity for a solution containing 0.34 moles of NaNO3 dissolved in 0.5 liter of
water.
Answer:
0.68 mol/L
Explanation:
M=m/l
m is moles and l is liters
Since they gave us the values in the correct units, all we have to do it plug it in
M=0.34 mol/0.5 liters
M=0.68
How many atoms of cobalt are in 4 moles of cobalt?
2 × 10²⁴ atoms Co
General Formulas and Concepts:Math
Pre-Algebra
Order of Operations: BPEMDAS
Brackets Parenthesis Exponents Multiplication Division Addition Subtraction Left to RightChemistry
Atomic Structure
Reading a Periodic TableAvogadro's Number - 6.022 × 10²³ atoms, molecules, formula units, etc.Stoichiometry
Using Dimensional AnalysisExplanation:Step 1: Define
4 mol Co (Cobalt)
Step 2: Identify Conversions
Avogadro's Number
Step 3: Convert
Set up: [tex]\displaystyle 4 \ mol \ Co(\frac{6.022 \cdot 10^{23} \ atoms \ Co}{1 \ mol \ Co})[/tex]Multiply/Divide: [tex]\displaystyle 2.4088 \cdot 10^{24} \ atoms \ Co[/tex]Step 4: Check
Follow sig fig rules and round. We are given 1 sig fig.
2.4088 × 10²⁴ atoms Co ≈ 2 × 10²⁴ atoms Co
A gas at 127 celsius and 10.0 L expands to 20.0 L. What is the new
temperature in kelvin? (You must convert to Kelvin before calculating
this problem
Answer:
T₂ = 800 K
Explanation:
Given that,
Initial temperature of the gas, T₁ = 127°C = 400 K
Initial volume, V₁ = 10 L
Final volume, V₂ = 20 L
We need to find the new temperature.
The volume of a gas is directly proportional to its Kelvin temperature.
Let T₂ is the new temperature. So,
[tex]\dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}\\\\T_2=\dfrac{V_2T_1}{V_1}\\\\T_2=\dfrac{20\times 400}{10}\\\\T_2=800\ K[/tex]
So, the new temperature of the gas is 800 K.
A typical tincture of iodine contains about 2.0% iodine by mass. Calculate
the mass of iodine in a 500. g tincture.
How many atoms of oxygen are in a molecule
of
glucose (C6H1206)?
Be sure to use the correct place value.
Answer:
Um... 6
Explanation:
C6H12O6
The O is oxygen and the 6 is the exact number of atoms
What is the molecular formula for C5H7 if its molar mass is 536 g/mol?
Answer:
(C5H7)8
Explanation:
It's empirical formula is given as; C5H7
Molar mass of carbon(C) = 12 g/mol
Molar mass of hydrogen(H) = 1 g/mol
We are told that it's molar mass is 536 g/mol.
To find the molecular formula;
Molecular formula = n × empirical formula
Thus;
n = 536/((12 × 5) + (1 × 7))
n = 8
Thus;
Molecular formula = (C5H7)8
Determine el número de moles presentes en una esfera de titaniode 0.5 cm de radio, sabiendo que la densidad del titanio es de 4507kg/m³. =433
Answer:
0.0493 moles de Titanio
Explanation:
Primero, debemos hallar el volumen de la esfera. Usando la densidad podemos hallar la masa de titanio y usando la masa atómica encontraremos las moles de titanio:
Volumen de la esfera:
Volumen esfera = 4/3π * Radio³
Volumen = 0.5236cm³
En m³ (1m³ = 1x10⁶cm³):
0.5236cm³ * (1m³ / 1x10⁶cm³) = 5.36x10⁻⁷m³
Masa en gramos:
5.36x10⁻⁷m³ * (4507kg / m³) = 2.36x10⁻³kg * (1000g / 1kg) = 2.36g de Titanio
Moles -Masa molar Ti: 47.867g/mol-:
2.36g de Titanio * (1mol / 47.867g) =
0.0493 moles de TitanioHow moles are in 45.7g of CH3?
first find the atomic weight of CH3 which would be
atomic weight: 12.011 (3×1.008) = 36.32 g/mol
then find the moles in the given mass
36.32 ÷ 45.7 = 0.794
I HOPE I'M NOT WRONG I HAVENT DONE CHEM IN SO LONG
____ NaF + ____ Br2 à ____ NaBr + ____ F2
A. ---, 2, 2, ---
B. 2, ---, ---, 2
C. 2, ---, 2, ---
Answer:
2 NaF + Br2 --> 2NaBr + F2
Explanation:
Well first I notice that there are two flourines on the products side so we need to put a 2 of NaF. Now there are 2 sodiums on the products side so we have to put another two in front of NaBr.
2 NaF + Br2 --> 2NaBr + F2
PLS HELPPP ASAP
According to the Periodic Table of Elements, the neutral atom of what element has 4
protons, 5 neutrons, and 4 electrons?
O A. beryllium
O B. boron
OC. fluorine
D. aluminum
A gas at a pressure of 360 torrs and a volume of 750 ml. If the pressure becomes 1.5 atm what is the new volume?
Answer:
V₂ = 236.84 mL
Explanation:
The relation between pressure and volume is inverse.
We can write it as follows :
[tex]P_1V_1=P_2V_2[/tex]
We have,
P₁ = 360 torrs, V₁ = 750 mL, P₂ = 1.5 atm = 1140 torr.
So,
[tex]V_2=\dfrac{P_1V_1}{P_2}\\\\V_2=\dfrac{360\times 750}{1140}\\\\V_2=236.84\ mL[/tex]
So, the new volume of the gas is 236.84 mL.
This image models…
diffraction
reflection
refraction
absorption
Answer:
reflection is correct answer by my views
When kci dissolved in ethanol what is the intermolecular attraction between k+ ions and ethanol molecules
Answer:
ion-dipole interaction
Explanation:
Ethanol is a polar molecule due to the presence of the polar O-H group in the molecule. This means that the molecule has a dipole moment.
The positive end of the dipole lies on hydrogen while the negative end of the dipole lies on oxygen.
When KCl is dissolved in ethanol, K^+ ions can interact with the negative end of the dipole in ethanol by ion-dipole interaction.
A neutral atom has 12 protons. In chemical bonding, which is the most likely charge of the ion?
A. 2+
B. 1+
C. 2-
D. 6-
Students are completing an investigation on types of heat transfer. For one part of the investigation, they place their hand on a cool window and feel the difference in thermal energy. When they are touching the glass, what type of heat transfer are they experiencing?
a .Conduction
b. Convection
c. Radiation
For the reaction
? P4+? S8 - ? P4S10
what is the maximum amount of P4S10 which
could be formed from 15.29 g of P4 and 17.66 g
of Sg?
Answer in units of g.
Please hurry it’s due today and include the steps if you can
Is the process represented below an example of a physical or a chemical
change?
CO2(s) —» CO2(g)
Jay painted the inner four walls of a box. Then he put an ice block into it such that it did not touch the walls, but he couldn't do the same when he put water in that box. Why?
Answer:
Liquid takes the shape of container, so it will always touch the walls of the box in which you put it.
Explanation:
We know that a solid has a definite shape and a definite volume hence it occupies only its own volume in the box, it does not touch the walls of the box.
However, a liquid does not have a definite shape and volume. It occupies the volume of the box. Therefore, the liquid water must definitely touch the walls of the box.
Explain what a catalyst is and give an example of a transition as one.
Answer:
Catalyst, in chemistry, any substance that increases the rate of a reaction without itself being consumed.
...
Catalyst.
process catalyst
ammonia synthesis iron
sulfuric acid manufacture nitrogen(II) oxide, platinum
cracking of petroleum zeolites
Will mark brainiest!!!! Also I posted other questions
Answer:
Crash sensors measure how quickly a vehicle slows down in a frontal crash or accelerates to the side in a crash Some vehicles are equipped with a sensing system designed to detect the onset of a rollover crash Rollover crash sensors may be located in the ecu or at the center of the vehicle
The the Crash trip sensors in cars that send an electric signal to an ignitor The heat generated causes sodium azide to decompose into sodium and nitrogen gas which inflates the airbags
Explanation:
have a nice day
What is the SI unit of time?
A.
second
B.
minute
C.
hour
D. day
Answer:
option a. second
.............
Some seawater is evaporated. The sea salt obtained is found
to be 86% sodium chloride. How much sodium chloride
could be obtained from 200 g of this salt?
Answer:
the answer is 172g
Explanation:
200 × 0.86 = 172g
how many molecules are in SO4
Answer:
there are 5 molecules in SO⁴
what is an acid containg oxygen?
Explanation:
An oxyacid, oxoacid, or ternary acid is an acid that contains oxygen. Specifically, it is a compound that contains hydrogen, oxygen, and at least one other element, with at least one hydrogen atom bonded to oxygen that can dissociate to produce the H+ cation and the anion of the acid.
Answer:
oxyacid, oxoacid
Explanation:
An oxyacid, oxoacid, or ternary acid is an acid that contains oxygen. Specifically, it is a compound that contains hydrogen, oxygen, and at least one other element, with at least one hydrogen atom bonded to oxygen that can dissociate to produce the H+ cation and the anion of the acid.
What do plants need in order to make food?
A. water, energy, oxygen
B.carbon dioxide, energy, oxygen
C.water, energy, carbon dioxide
D.water, oxygen, carbon dioxide
Answer:
Water, solar energy, carbon dioxide
Explanation:
what is the smallest unit of NaCl?
Answer:
A molecule of Nacl
Maybe