The answer is -30 N
The explanation:
- to make the box move. so,the horizontal force must be greater than the frictional force.
-and when the horizontal force applied is 30 N. So, the box will remain stationary if the frictional force is equal in magnitude but opposite in direction to the horizontal force. means frictional force = -30 N
This is also being indicate that vertical force due to gravity is equivalent to the normal force when gravity force = 8 N and normal force =8 , meaning the box does not move vertically.
Read more on Brainly.com - brainly.com/question/4162941#readmore
the answer is -30*N.................
A 35.65 g sample of NaOH contains 0.8910 moles of NaOH.
The mole, denoted by the sign "mol," is the volume of a system that has the same number of atoms in 0.012 kilograms of carbon-12 as there are elementary particles.
The mole, often known as mol, is a SI unit used to measure how many particles are present in a given substance. A mole is made up of 6.02214179 atoms or other fundamental building blocks like molecules.
Mass off NaOH = 39.997
given = 35.65 g of NaOH
No of moles of NaOH =35.65 g of NaOH × 1 mol NaOH /40.01 g
No of moles of NaOH = 0.8910 moles.
To know more about mole visit:
#SPJ2
Answer:
0.8910 mols of NaOH in a 35.65 g sample of NaOH
Explanation:
Mass off NaOH = 39.997
given = 35.65 g of NaOH
35.65 g of NaOH * 1 mol NaOH = 0.8910, since there are 4 sig figs.
/40.01 g
Answer:
2.53 grams of hydrogen gas will be produced and 12.2 many grams of the excess reactant i.e. calcium will be left over.
Explanation:
Moles of calcium =
Moles of HCl =
According to reaction, 2 moles of HCl reacts with 1 mole of calcium :
Then 2.53 moles of HCl will recat with :
of calcium.
As we can see moles of calcium are in excessive amount. Hence calcium is an excessive reagent.
Moles of calcium left unreacted =1.57 mol - 1.265 mol =0.305 mol
Mass calcium left unreacted = 0.305 mol × 40 g/mol =12.2 g
Since, calcium is an excessive reagent HCl is limiting reagent and the amount of hydrogen gas produced will depend on HCl .
According to reaction, 2 moles of HCl gives 1 mole of hydrogen gas.
Then 2.53 moles of HCl will give:
of hydrogen gas.
Mass of 1.265 mol of hydrogen gas = 1.265 mol × 2 g/mol = 2.53 g
2.53 grams of hydrogen gas will be produced and 12.2 many grams of the excess reactant i.e. calcium will be left over.
Answer:
2.55 g of hydrogen
12.17 g calcium.
to nearest hundredth.
Explanation:
The balanced equation is:
Ca + 2HCl ---> CaCl2 + H2
Using the atomic masses
40.078 g Ca react with 72.916 g of HCl to give 2.016 g HCl
The ratio of Ca to HCl in the above is 1 to 1.81935
so 62.8 g Ca reacts with 62.8 * 1.81935 = 114.245 g HCl
so there is excess of Ca in the given weights.
Therefore the mass of Hydrogen produced
= (2.016 / 72.916) * 92.3
= 2.552 g of hydrogen gas.
The mass of calcium required to produce 2.552 g of hydrogen is:
(2.552 / 2.016) * 40.078
= 50.73 g
So the excess of calcium is 62.8 - 50.73
= 12.17 g.
The concentration of gallium in kilograms per cubic meter is equal to the calculated mass of gallium per cubic meter.
To determine the concentration of gallium in kilograms per cubic meter, we need to convert the concentration from atomic percent (at%) to kilograms per cubic meter.
The atomic fraction is the ratio of the number of gallium atoms to the total number of atoms in the silicon-gallium mixture.
We need to know the atomic masses of gallium and silicon. The atomic mass of gallium is 69.72 g/mol, and the atomic mass of silicon is 28.09 g/mol.
The atomic fraction of gallium can be calculated using the formula:
Atomic fraction of gallium = (Concentration of gallium in at%) / (Atomic mass of gallium) / [(Concentration of gallium in at%) / (Atomic mass of gallium) + (Concentration of silicon in at%) / (Atomic mass of silicon)]
Plugging in the given values:
Atomic fraction of gallium = (%) / (69.72 g/mol) / [(at%) / (69.72 g/mol) + (100 - ) at% / (28.09 g/mol)]
Now, let's convert the atomic fraction to the number of gallium atoms per cubic meter. We can use Avogadro's number, to make this conversion.
Number of gallium atoms per cubic meter = Atomic fraction of gallium × Avogadro's number.
Mass of gallium per cubic meter = Number of gallium atoms per cubic meter × (Atomic mass of gallium / 1000)
Therefore, the concentration of gallium in kilograms per cubic meter is equal to the calculated mass of gallium per cubic meter.
Learn more about Concentration here;
#SPJ12
The concentration of gallium in kilograms per cubic meter can be calculated using the atomic mass of gallium and Avogadro's number.
To calculate the concentration of gallium in kilograms per cubic meter, we can use the atomic mass of gallium and Avogadro's number. The concentration in kilograms per cubic meter can be found using the formula:
Concentration (kg/m³) = Concentration (% by mass) x Density (g/cm³) x Atomic Mass (g/mol) / 1000 x Avogadro's Number
First, convert the concentration from at% (atomic percent) to % by mass. Since gallium has an atomic mass of 69.7 g/mol, we can use this value to find the concentration in kilograms per cubic meter.
#SPJ3
b. 3
c. 5
d. 6
It would be: 2*3 = 6 oxygen atoms
OPTION D IS YOUR ANSWER......
The polarity of a water molecule comes from the uneven distribution of electron density of hydrogen and oxygen atom. The oxygen in the water molecule is more electronegative than the hydrogen. Water has a partial positive charge near the hydrogen atom and a partial negative charge near the oxygen atom. The result of this electrostatic attraction results in the bond called hydrogen bond. Also, because of this bond, it has the ability to dissolve most of the solutes due to its polarity and bonding.