Answer:
<h3>The answer is 0.1 mol</h3>
Explanation:
To find out the number of moles we use the formula

where
n is the number of moles
M is the molar mass
m is the mass of the substance
From the question
m = 400 g
M of Ca = 40 g/mol
We have

We have the final answer as
<h3>0.1 mol</h3>
Hope this helps you
True, to convert from moles to atoms, multiply the molar amount by Avogadro's number. To convert from atoms to moles, divide the atom amount by Avogadro's number (or multiply by its reciprocal).
Answer:
NO will be the limiting reagent.
Explanation:
The balanced equation is:
2 NO + 2 CO → N₂ + 2 CO₂
By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:
- NO: 2 moles
- CO: 2 moles
- N₂: 1 mole
- CO₂: 2 moles
Being the molar mass of each compound:
- NO: 30 g/mole
- CO: 28 g/mole
- N₂: 28 g/mole
- CO₂: 44 g/mole
Then by stoichiometry the following quantities of mass participate in each reaction:
- NO: 2 moles* 30 g/mole= 60 g
- CO: 2 moles* 28 g/mole= 56 g
- N₂: 1 mole* 28 g/mole= 28 g
- CO₂: 2 moles* 44 g/mole= 88 g
The limiting reagent is one that is consumed first in its entirety, determining the amount of product in the reaction. When the limiting reagent is finished, the chemical reaction will stop.
To determine the limiting reagent, you can use a simple rule of three as follows: If 56 grams of CO react with 60 grams of NO, 3 grams of CO react with how much mass of NO?

mass of NO= 3.21 grams
But 3.21 grams of NO are not available, 3 grams are available. Since you have less moles than you need to react with 3 grams of CO, <u><em>NO will be the limiting reagent.
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Answer:
1) K and Rb
2) 20 protons, 20 neutrons, and 20 electrons.
Explanation:
1) If it's in the same column, it has the same # of valence electrons (e- on the outer shell), therefore similar chemical properties.
2)
1) atomic #, 20, is the number of protons
2) subtract the mass number from # of protons, which you get 20 neutrons
3) Number of electrons in a neutral atom = number of electrons, which is 20. You can also check yourself by looking at electron configuration on a full periodic table.
Answer:
The rate of the catalyzed reaction will increase by a 1.8 × 10⁵ factor.
Explanation:
The rate of a reaction (r) is proportional to the rate constant (k). We can find the rate constant using the Arrhenius equation.

where,
A: collision factor
Ea: activation energy
R: ideal gas constant
T: absolute temperature (125°C + 273 = 398 K)
For the uncatalized reaction,

For the catalized reaction,

The ratio kC to kU is 6.0 × 10⁻⁸A/3.4 × 10⁻¹³A = 1.8 × 10⁵