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## How many protons are in the nucleus of an atom?

Some nitrogen atoms have an atomic mass number of 15 (A=15). A is the number of neutrons plus protons in the nucleus. However, we already know that there are 7 protons….

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Calling names The Big Bang
Counting in the nucleus Atoms at last
Neutrons and isotopes
Putting things in order

## What element has 4 protons 4 electrons and 6 neutrons?

Atomic Number

Name Protons Neutrons
Lithium 3 4
Beryllium 4 5
Boron 5 6
Carbon 6 6

## How many protons and electrons does a neutral atom of beryllium have?

(Round the atomic mass from the periodic table to the nearest whole number to get part of your answer.) From the periodic table, beryllium has an atomic number of 4 and a mass of almost 9 amu. Therefore, a neutral beryllium atom has 4 protons, 4 electrons, and 5 neutrons (# neutrons = mass # – # protons).

## How many protons does beryllium 11 contain?

Both atoms have the same mass number, namely 7. However, the nucleus of the lithium atom has three protons and four neutrons, while the nucleus of the beryllium atom has four protons and three neutrons.

## Why does Cu show positive electrode potential?

Copper has lower tendency than hydrogen to form ions, so if the standard hydrogen electrode is cconnected to the copper half-cell, the copper will be relatively less negative. The copper electrode has relatively lower number of electrons. so it has positive electrode potential.

## Why is E value of Cu positive?

Copper has a high energy of atomisation but a low hydration energy due to which the E0 value for Cu is positive.

## Why is e value for mn3 +/ mn2+?

Because Mn3+ has the outer electronic configuration of 3d4 and Mn2+ has the outer electronic configuration of 3d5. Thus, the conversion of Mn3+ to Mn2+ will be a favourable reaction since 3d5 is a very stable configuration as it is half filled configuration. Hence, Eo value for Mn3+ / Mn2+ couple is positive.

## What does negative electrode potential mean?

So, if an element or compound has a negative standard electrode reduction potential, it means it forms ions easily. The more negative the value, the easier it is for that element or compound to form ions (be oxidised, and be a reducing agent).

## Why iron has higher enthalpy of atomization than copper?

Copper has outer electronic configuration of 3d104s1 and 1 unpaired electron. Iron has more number of unpaired electrons than copper. Hence, Iron has higher enthalpy of atomisation than that of copper.

## Which element has highest enthalpy of atomisation in 3d series?

Sc & zn belongs to 3rd group pf periodic table. The extent ofmetallic bonding an elementundergoes decides the enthalpy of atomization. The more extensive the metallic bonding of an element, the more will be its enthalpy of atomization.

## Why enthalpy of atomisation of zinc is lowest?

The enthalpy of atomization depends on the extensive metallic bonding which in turn depends on the number of unpaired electrons. Due to the absence of these unpaired electrons in Zn. The interatomic bonding is weak in Zn and hence the enthalpy of atomization of Zn is the lowest.

[Ar] 3d6 4s2

2021-06-17