Answer: 3d
Explantion:
1) Period 4 contains the elements with atomic numbers 19 through 36.
2) The elements with atomic numbers 19 (K) and 20 (Ca) fill the orbital 4s.
3) After that, as Aufbau's rule may help you to remember, the energy of the orbitals 3d is lower than the energy of the orbtitals 4p. So, the element 21 (Sc) start fillind the orbital 3d.
There are ten 3d orbitals, so the elements 21 through 30 fill the 3d orbitals.
Those elements, called transition metals are: Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, and Zn.
When the 3d orbitals are full, the next elements in the same period 4, fill the six 4p orbitals.
Answer:
Compound
Explanation:
We want to know if it's a compound or a mixture.
An example of a mixture is salt water: you can heat it hot enough to boil off the water, leaving only the salt. This is a physical change, which is how you know it's a mixture.
Something like gold is a compound: if you heat it, or hit it, you'll still only have gold. You can only break it down by chemical means, which is how you know it's a compound.
C+2H2 -------> CH4
from reaction 2 mol 1 mol
from the problem x mol 10 mol
x=2*10/1 = 20 mol
Answer: 20 mol of H2.
Answer:
The answer is
<h2>0.087 g/mL</h2>
Explanation:
The density of a substance can be found by using the formula

From the question
mass of liquid = 2.6 g
volume = 30 mL
The density is

We have the final answer as
<h3>0.087 g/mL</h3>
Hope this helps you
wavelenghts are lengths. they are measured in distances.