why scientist use the international system of units
Explanation:
it allows scientists from disparate regions to use a single standard in communicating scientific data without vocabulary confusion.
What is the freezing point in °C) of a 0.743 m
aqueous solution of KCI?
Enter your rounded answer with
3 decimal places.
K; for water = 1.86 °C/m
Answer:
2.764 °C
Explanation:
ΔT = 2 x 1.86 C/m x 0.743m = 2.764C That means the freezing point of the solution is 2.764C less than the pure solvent (water)
Water is dipolar because:
A. It has two hydrogens, each of which pulls oxygen's electrons and separates the
charges into two areas.
B. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a
slight negative and hydrogens a slight positive charge.
C. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a
slight positive and hydrogens a slight negative charge.
OD. It has two hydrogens, each of which has its own polar area.
Answer:
B. Oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a slight negative and hydrogens a slight positive charge.
Explanation:
In the water molecule (H2O), an oxygen atom is bonded to two hydrogen atoms. Oxygen atom is much more electronegative (has more attraction for electrons) than hydrogen atom, hence, it pulls electrons from one one of the hydrogen atoms bonded to it making it more negatively charged and the hydrogen atom, more positively charged.
The possession of positive charge (+) and negative charge (-) in the same molecule, caused by uneven flow of electrons is what it means to be DIPOLAR (from dipole). Hence, water is DIPOLAR because oxygen pulls electrons closer to itself than hydrogens, giving the oxygen a slight negative and hydrogens a slight positive charge.
what is the most appropriate unit to measure the following; the length of a football field. b) the diameter of a tennis ball
Explanation:
a) m (metre)
b) mm (millimeter)
Consider two gases, A and B, which are in a container at room temperature. What effect will the following changes have on the rate of the reaction between these gases?
The temperature is decreased at a constant volume.
A. Increase
B. Decrease
Answer:
A. The rate of reaction will increase or go up
B. The rate of reaction will decrase or go down.
Explanation:
Increasing the temperature will make the gas particles move faster. Faster movement will increase rate of collision between particles to cause a reaction. Decreasing the temperature will cause the opposite to happen.
Which of the following has maximum number of atoms?
(a) 18 g of H2O
(b) 18 g of O2
(c) 18 g of CO2
(d) 18 g of CO4
Answer:
(a) 18 g of H2O
Explanation:
The molecule with great number of moles will have great number of atoms.
By observation, since all compounds have same mass, water has the least molcular mass
[tex]H_{2} O = \: 18 \: g[/tex]
Answer:
18g of H2O
Explanation:
the molecule with great number of moles will have great number of atoms .
(a) option is correct
what is the balanced equation of 2HCl + Mg - MgCla + Ha
2HCl + Mg => MgCl2 + H2
Molar mass calculation for Cl^2
Answer:
Mass of Cl = 35.5
Mass of Cl2 => 35.5×2
=> 71 g/mol
hope that helps ✌
71
explain:The atomic mass of chlorine is equal to the molar mass of chlorine so the molar mass of chlorine is 35.5
=> molar mass for Cl^2: 35,5*2=71
Determine the mass of oxygen in a 45.0 g sample of calcium carbonate
Answer:
The mass of oxygen in 45.0 g sample of calcium carbonate is approximately 21.58 g
Explanation:
The chemical formula for calcium carbonate is CaCO₃
The molar mass of CaCO₃ = 100.0869 g/mol
The mass of oxygen in one mole of CaCO₃ = 3 × 15.999 g = 47.997 g
The mass of oxygen in 45.0 g sample of CaCO₃, m, is goven as follows;
m = 45.0/100.0869 × 47.997 g ≈ 21.58 g
The mass of oxygen in 45.0 g sample of calcium carbonate, m ≈ 21.58 g
aluminum hydroxide molecular weight step by ste
While driving her car on a hot sunny day, a woman was struck in the back of the neck by the dough from an exploding can of Pillsbury biscuits. From the sound it made and the feeling of warm sticky dough on her neck, she thought she had been hit by a bullet! Describe the likely conditions that caused this to happen. Be sure to explain AT THE MICRO scale how the particles were affected.
Answer:
The dough is made from flour sugar, baking soda, sometimes yeast. The sugar is converted into gaseous products including carbon dioxide, CO₂ and alcohols. As more gases are produced, the pressure increases, and according to Charles's law, as the temperature on a sunny day is higher than on a cool day, the pressure of the gases increases further, to the point that the can containing the biscuits can not hold the pressure, leading to an explosion
Explanation:
which of the following has more atoms 3.14 g Cu or 1.10 g of H? Explain
list from soft to hard
List the following minerals in order from softest to hardest:
apatite, calcite, talc, quartz, diamond.
The volume of a gas was 48 mL when the temperature was 159.6 ºC. If the temperature was initially 4.9 ºC, and there was no change in the pressure, what was the initial volume of the gas?
According to Charles law
[tex]\boxed{\sf \dfrac{V_1}{T_1}=\dfrac{V_2}{T_2}}[/tex]
[tex]\\ \sf\longmapsto \dfrac{48}{159.6}=\dfrac{V_2}{4.9}[/tex]
[tex]\\ \sf\longmapsto V_2=\dfrac{48\times 4.9}{159.6}[/tex]
[tex]\\ \sf\longmapsto V_2=\dfrac{235.2}{159.6}[/tex]
[tex]\\ \sf\longmapsto V_2=1.4mL[/tex]
Which reaction occurs at the cathode in an electrochemical cell?
A. Cu(s) → Cu2+(aq) + 2e
B. Cu2+(aq) + H2(g) → Cu(s) + 2H+(aq)
C. Cu(s) + 2H+(aq) → Cu2+(aq) + H2(g)
D. Cu2+(aq) + 2e → Cu(s)
Answer:
I could be wrong but I say it's letter b
Explanation:
I hope you have an great night
what effect does smiling on at teacher mean when given no homework mean please give me an answer thanks guys
Answer:
no n o n o n o nonono in o no n o n I n jo n b
Explanation:
no no no no no no n on on on I I j
calculate the mass of magnesium needed to make 25g of magnesium oxide
Explanation:
here's the answer to your question about
Which statement describes the VSEPR theory?
A.
Electron pairs in the valence shell of an atom have a tendency to attract other nearby electron pairs.
B.
Electrons in the valence shell of an atom exert a repulsive force on other atoms while forming a chemical bond.
C.
Electron pairs in the valence shell of an atom exert a repulsive force on all other electron pairs in the valence shell of the atom.
D.
Electrons in the valence shell exert a repulsive force while completing their octet during the formation of chemical bond.
Answer:
A.
Electron pairs in the valence shell of an atom have a tendency to attract other nearby electron pairs.
Hope it helps you.Propane can be cracked to produce propane and hydrogen. Complete the symbol equation for the reaction.
Answer:
Explanation:
C3H8= C3H6 +H2
c. What is Cytoplasm? What does it contain?
Answer:
Cytoplasm is the space between cell membrane and nuclear membrane filled with a translucent liquid . It contains carbohydrates , proteins , lipids , nucleic acids , sodium and pottassium salts , water and enzymes .
Which statement is true?
1. Heat refers to a process.
2. Thermal energy refers to a process.
3. Thermal energy refers to a single particle.
4. Heat refers to a quantity.
Answer:
4. Heart refers to a quantity
Answer:
Heat Refers To A Process
A sample of oxygen gas has a volume of 453.7 mL when its pressure is 0.435 atm. What will the volume of the gas
be
at a pressure of 0.88 atmospheres, if the temperature remains constant?
Answer:
is you'r question correctly?
or not
To convert from one metric unit to another metric unit is done simply by moving the decimal place the appropriate amount of places.
Example: 2.5 cm = 25 mm
true or false?
Answer: true
Explanation:
2.5 cm does = 25mm
Answer:
True
Because, all of these metric units differ from one another by a multiple of 10.
A report on the various water conservation methods used by any one
states of India
Answer:
Kuls are diversion channels that carry water from a glacier to village. Often spanning long distances, with some over 10 km long, kuls have been around for centuries. They are the lifeline of people of Spiti valley of Himachal Pradesh and in Jammu too.
Kul starts at the glacier, which is to be tapped. Keeping the head clear of debris is achieved by lining the sides of Kul with stones which ensure that there is no seepage or clogging. The Kul leads to the village where the water is stored in a circular water tank. The water is drawn from here are per the need of the village.
Explanation:
Here is a list of some of the traditional water conservation methods that are still in use:
What Chemicals including in Cosmetic?
The chemicals including in cosmetic are:-
1.Talcum Powder
2.Nanoparticles
3.Coal Tar
4.Triclosan
5.Toluene
Hope this helps you.
Which atom is abundant on earth
Answer:
Oxygen
Explanation:
Oxygen is abundant on earth
What is the electron configuration for fluorine?
Answer:
1s2 2s2 2p5
step by step:
Answer:
Electron configuration using subshell;
1s² 2s² 2p⁵
using main shell ie;
2,7
Balance in basic solution: O2(g) + Cr³+ (aq) → H₂O2 (1) + Cr₂O7²- (aq)
cr2o72+H2o2-(r3+o2)
Explanation:
r62o72+H2o2-(r3+o2)
Question 2: thanks!!!
b. What chemist finds
out how much nitrogen is in a sample of air
