Exothermic reactions release heat the surrounding. So Freezing?
Molarity
a. Na2CO3
Molar mass = 106 g/mol
n= 109 g / (106 g/mol) = 1.028 mol
b. 6.00L
c. M=n/V
M = 1.028 mol / 6.00 L
M= 0.1713 mol / L
Answer: The molarity of the sodium carbonate solution is 0.1713 mol/L
By state of matter I assume you mean solid, liquid, gas, in which case the answer would be C.
the behaviour of molecules:
- in a solid is low energy with limited activity where molecules only vibrate, cannot mould to shape of container
- in a liquid is with moderate energy, with molecules flowing over the top of one another, and thus can mould to the shape of the container
- in a gas is high energy with much activity, molecules "fly" around the container they are in and can be compressed
Answer:
Option A. 0.378M
Explanation:
Data obtained from the question include:
Molarity of acid (Ma) =..?
Volume of acid (Va) = 37.0 mL
Volume of base (Vb) = 56.0 mL
Molarity of base (Mb) = 0.250 M
Next, we shall write the balanced equation for the reaction. This is given below:
HCl + NaOH —> NaCl + H2O
From the balanced equation above,
The mole ratio of the acid (nA) = 1
The mole ratio of the base (nB) = 1
Finally, we can determine the molarity of the acid as shown below :
MaVa/MbVb = nA/nB
Ma x 37 / 0.25 x 56 = 1
Cross multiply
Ma x 37 = 0.25 x 56
Divide both side by 37
Ma = 0.25 x 56 /37
Ma = 0.378M
Therefore, the molarity of the acid, HCl is 0.378M
Answer:
Mass = 32.13 g
Explanation:
Given data:
Mass of water produced = 30 g
Mass of nitric acid needed = ?
Solution:
Chemical equation:
4Zn + 10HNO₃ → 4Zn(NO₃)₂ + NH₄NO₃ + 3H₂O
Number of moles of water:
Number of moles = mass/molar mass
Number of moles = 30 g/ 18 g/mol
Number of moles = 1.7 mol
Now we will compare the moles of water with nitric acid.
HNO₃ : H₂O
10 : 3
1.7 : 3/10×1.7 = 0.51 mol
Mass of nitric acid:
Mass = number of moles × molar mass
Mass = 0.51 mol × 63.01 g/mol
Mass = 32.13 g
