Answer:
Air is a qualified element
Answer:
16% v/v es la nueva concentración de alcohol en la solución
Explanation:
El porcentaje volumen/volumen (% v/v) es definido como 100 veces la relación entre el volumen de soluto (Alcohol en este caso) y el volumen total de la solución (Agua + Alcohol). Para resolver esta pregunta necesitamos hallar el volumen de alcohol y el de agua:
<em>Volumen alcohol:</em>
320cc * (20cc etanol / 100cc) = 64cc etanol
<em>Volumen agua:</em>
80cc + (320cc-64cc) = 336cc agua
<em>% v/v:</em>
64cc / (336cc + 64cc) * 100
= 16% v/v es la nueva concentración de alcohol en la solución
Answer: 
Explanation:
Alpha Decay: In this process, a heavier nuclei decays into lighter nuclei by releasing alpha particle. The mass number is reduced by 4 units and atomic number is reduced by 2 units.
General representation of an element is given as:
where,
Z represents Atomic number
A represents Mass number
X represents the symbol of an element
General representation of alpha decay :
The balanced nuclear equation when the isotope Strontium-90 decays by Q- decay is :

The chemical reaction is written as:
2Zn + O2 = 2ZnO
We are given the amount of the product to be produced from the reaction. We use this value and the relation of the substances in the reaction to calculate what is asked. We do as follows:
2.10 g ZnO ( 1 mol / 81.408 g ) ( 1 mol O2 / 2 mol ZnO ) ( 32 g / 1 mol ) = 0.414 g O2 is needed
Hi there
In order for an electron to jump into a higher energy state, it must first absorb energy (heat, light, etc).
When an electron goes back down to the ground state from the excited state, it emits energy usually in the form of a photon.
i hope this helps