Out of the options, the best indicator is a color change since it is the only one that can't really be blamed on a physical change. you will eventually notice that during qualitative labs and some quantitative labs, usually the thing that you are looking for is either color change or the production of a precipitate to indicate the presence of a chemical reaction
I would say compression or the absence of heat because heating a liquid makes it a gas<span />
Answer:
Aluminium.
Explanation:
The above electronic configuration can be written in a simplified form as shown below:
1s² 2s²2p⁶ 3s²3p¹
Next, we shall determine the number of electrons in the atom of the element as follow:
Number electron = 2 + 2 + 6 + 2 + 1
Number of electron = 13
Next, we shall determine the number of protons.
Since the element is in its neutral state,
The number of electrons and protons are equal i.e
Proton = Electron
Number of electron = 13
Proton = Electron = 13
Proton = 13
Next, we shall determine the atomic number of the element.
The atomic number of an element is simply the number of protons in the atom of the element i.e
Atomic number = proton number
Proton = 13
Atomic number = 13
Comparing the atomic number of the element with those in the periodic table, the element with the above electronic configuration is aluminium since no two elements have the same atomic number.
Answer:
Explanation:
use this fromula
q = m c ∆t
m is mass of silver =50 g
∆t is difference in temperature= 255-106=149
C= specific heat fo silver ( should be mentioned in your question )
Answer:
2H₂ + O₂ → 2H₂O
Explanation:
The expression of the equation is given as:
_H₂ + 2O₂ → 2H₂O
Now for expression above,
Reactants Products
H 2 4
O 4 2
to balance the equation, we use 2 moles of hydrogen gas and 1 mole of oxygen gas;
2H₂ + O₂ → 2H₂O
