Answer:
B
Explanation:
The cell membrane cannot receive or recognize chemical signals
Answer:
Q = 5254.39 J
Explanation:
Given that,
Mass of ethanol, m = 68.8 g
The temperature increases from 40.0°C to 71.3°C.
The specific heat of ethanol is 2.44 j/g°C
We need to find the heat absorbed by the ethanol. We know that the heat absorbed due to the change in temperature is given by :
Put all the values,
So, 5254.39 J of heat is absorbed by Ethanol.
Answer:
Explanation:
Sodium and potassium are present in group 1A. Both are alkali metals.
The atomic number of sodium is 11 and potassium is 19. Sodium is present in period 3rd while potassium is present in period 4th.
Electronic configuration of sodium:
Na₁₁ = 1s² 2s² 2p⁶ 3s¹
K₁₉ = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
It can be seen in electronic configuration that in case of sodium the valance electron is present in third energy level while in case of K outer most electron is present in 4th energy level. So atomic structure of sodium has three energy level and K has four energy level that's why radius of potassium is greater than sodium because its the distance from center to outer most electronic shell.
Moreover as we move down the group atomic radii increased with increase of atomic number. The addition of electron in next level cause the atomic radii to increased. The hold of nucleus on valance shell become weaker because of shielding of electrons thus size of atom increased.
Answer:
it is an acid base reaction. the salt formed is calcium nitrate why zinc wont react with lead is that it is more reactive than calcium
Answer:
Explanation:
Hello,
In this case, the rest of statement is missing, therefore, it was found to be:
We add 100 ml of 0.01 M Na₂SO₄-solution to 100 ml of 0.02 M CaCl₂-solution. A precipitate of CaSO₄ is formed. What is the (minimal) volume of 0.01 M Na₂SO₄-solution that needs to be added to the mix for the CaSO₄ precipitate to be just dissolved completely? Consider CaSO₄ solubility constant to be 2.5x10⁻⁵
In this case, Ca⁺², SO₄⁻² and H₂O are out interest substance, thus, if we introduce 
as the additional volume of Na₂SO₄-solution, we've got:
Hence, we have:
![Ksp=[Ca^{+2}][SO_4^{-2}]=\frac{n_{Ca^{+2}}*n_{SO_4^{-2}}}{V_T} =2.5x10^{-5}](https://tex.z-dn.net/?f=Ksp%3D%5BCa%5E%7B%2B2%7D%5D%5BSO_4%5E%7B-2%7D%5D%3D%5Cfrac%7Bn_%7BCa%5E%7B%2B2%7D%7D%2An_%7BSO_4%5E%7B-2%7D%7D%7D%7BV_T%7D%20%3D2.5x10%5E%7B-5%7D)
Replacing the previous values:
Solving for , we obtain:
Best regards.
