Download App

Science [1 Mark Questions]

periodic classification of elements · Gujarat Board (GSEB) STD 10 (GSEB - English Medium). 66 questions.

Questions · Page 1 of 2

[1 Mark Questions]

🎯

Test yourself on this topic

50 questions · timed · auto-graded

Question 11 Mark
Two elements $M$ and $N$ belong to the same period of the modern periodic table and are in group $I$ and group $II$ respectively. Compare their following properties : $(a)$ Atomic size $(b)$ Metallic character $(c)$ Valency of oxides $(d)$ Molecular formula of their chlorides
Answer
  • $(a)$ Element $‘M’$ has larger atomic size than that of $‘N’.$
  • $(b)$ Element $‘M’$ possess more metallic character than that of $‘N’.$
  • $(c)$ Group I: Valency: $1$, Group $II:$ Valency $: 2$
  • $(d) MCI, MCl_2$
View full question & answer→
Question 21 Mark
How do you think the tendency to lose electrons changes in a group?
Answer
  • As we move from top to bottom in a group, the tendency to lose electrons increases.
View full question & answer→
Question 31 Mark
On which side of the periodic table do you find the non-metals?
Answer
  • Non-metals are present on the right side of the periodic table.
View full question & answer→
Question 41 Mark
On which side of the periodic table do you find the metals?
Answer
  • Metals are present on the left side of the periodic table.
View full question & answer→
Question 51 Mark
Examine elements of the third period and classify them as metals and non-metals.
Answer
  • The elements of the third period:
View full question & answer→
Question 61 Mark
Atomic radii of the elements of the second period are given below: Period II elements: $B \ Be \ O \ N \ Li \ C$ Atomic radius (pm)$: 88 \ 111 \ 66 \ 74 \ 152 \ 77$ Arrange them in decreasing order of their atomic radii.
Answer
  • Decreasing order of the atomic radii:
  • Period II elements: $Li> Be> B> C> N> O$
  • Atomic radius (pm):$152 \ 111 \ 88 \ 77 \ 74 \ 66$
View full question & answer→
Question 71 Mark
Which elements have the largest and the smallest atoms?
Answer
  • Lithium $(Li)$ has the largest and oxygen $(O)$ has the smallest atoms.
View full question & answer→
Question 81 Mark
What is the valency of magnesium with atomic number $12$ and sulphur with atomic number $16?$
Answer
  • Electronic configuration of Mg with atomic number $12$ is
  • $\begin{array}{c}\text { K L M } \\ 2\ \ \ 8\ \ \ 2\end{array}$
  • ∴ Valency of Mg $= 2$
  • Electronic configuration of S with atomic number $16$ is
  • $\begin{array}{c}\text { K L M } \\ 2\ \ \ 8\ \ \ 2\end{array}$
  • ∴ Valency of $S = 8 - 6 = 2$
View full question & answer→
Question 91 Mark
Write the positions of metallic, non-metallic and metalloid elements in the modern periodic table.
Answer
  • In the modern periodic table, metallic elements are on the left side while non-metallic elements are on the right side. Metalloids or semi-metals are in the middle of the periodic table.
View full question & answer→
Question 101 Mark
Are the elements now arranged in the pattern of a period in the periodic table?
Answer
  • Now, the above elements are arranged in the pattern of a period in the periodic table.
View full question & answer→
Question 111 Mark
From the following elements: ${ }_{20} \mathrm{Ca},{ }_3 \mathrm{Li},{ }_{11} \mathrm{Na},{ }_{10} \mathrm{Ne}(\mathrm{a})$ Select the element which has two shells, both of which are completely filled with electrons. (b) Select two elements of the same group.
Answer
  • (a) Element in which two shells are completely filled with electrons is $_{10}Ne (2, 8).$
  • (b) Two elements of the same group are ${ }_3 \mathrm{Li}(2,1)$ and ${ }_{11} \mathrm{Na}(2,8,1)$.
View full question & answer→
Question 121 Mark
Nitrogen (atomic number $7)$ and phosphorus (atomic number $15)$ belong to group $15$ of the periodic table. Write the electronic configuration of these two elements. Which of these will be more electronegative? Why?
Answer
  • The electronic configuration of nitrogen and phosphorus are as follows:
Element Atomic number Electronic configuration
$K L M$
Nitrogen $(N)$ $7$ $2 5 -$
Phosphorus $(P)$ $15$ $2 8 5$
  • Nitrogen is more electronegative than phosphorus because electronegative character decreases on moving down a group.
View full question & answer→
Question 131 Mark
By considering their position in the periodic table, which one of the following elements would you expect to have maximum metallic characteristics ? Ga Ge As Se Be
Answer
  • Among the given elements, Be and Ga will show maximum metallic characteristics.
  • Arrangement of given elements in different groups and periods is as follows
Group→ Period ↓ $1$ $2$ $13$ $14$ $15$ $16$
$1$ - - - - - -
$2$ - Be - - - -
$3$ - - - - - -
$4$ - - Ga Ge As Se
View full question & answer→
Question 141 Mark
In the modern periodic table, which are the metals among the first ten elements?
Answer
  • The first ten elements of the modern periodic table are as follows:
  • ${ }_1 \mathrm{H},{ }_2 \mathrm{He},{ }_3 \mathrm{Li},{ }_4 \mathrm{Be},{ }_5 \mathrm{B},{ }_6 \mathrm{C},{ }_7 \mathrm{N},{ }_8 \mathrm{O},{ }_9 \mathrm{F}$ and ${ }_{10} \mathrm{Ne}$.
  • Among these elements Li and Be are metals.
View full question & answer→
Question 151 Mark
How would the tendency to gain electrons change as you go down a group?
Answer
  • As we go down a group, the tendency to gain electrons decreases.
View full question & answer→
Question 161 Mark
How would the tendency to gain electrons change as you go from left to right across a period?
Answer
  • As we go from left to right across a period, the tendency to gain electrons increases.
View full question & answer→
Question 171 Mark
How will this tendency change in a period?
Answer
  • As we move from left to right in a period, the tendency to lose electrons decreases.
View full question & answer→
Question 181 Mark
How does the atomic size vary as you go down a group?
Answer
  • As we go down a group, the atomic size increases gradually.
View full question & answer→
Question 191 Mark
Name the elements which have the smallest and the largest atoms.
Answer
  • Lithium (Li) has the smallest atoms while Cesium (Cs) has the largest atoms.
View full question & answer→
Question 201 Mark
Study the variation in the atomic radii of first group elements given below and arrange them in an increasing order. Group I elements: Na Li Rb Cs K Atomic radius (pm): $186 \ 152 \ 244 \ 262 \ 231$
Answer
  • Increasing order of the atomic radii:
  • Group I elements: $Li< Na< K< Rb< Cs$
  • Atomic radius (pm): $152 \ 186 \ 231 \ 244 \ 262$
View full question & answer→
Question 211 Mark
How does the atomic radius change as you go from left to right in a period?
Answer
  • The atomic radii decreases as we move from left to right in a period.
View full question & answer→
Question 221 Mark
How were the positions of isotopes of various elements decided in the modern periodic table?
Answer
  • In the modern periodic table, positions of isotopes of different elements are not fixed separately.
  • Since the various isotopes of an element have the same atomic number, they are assigned the same position in the modern periodic table.
View full question & answer→
Question 231 Mark
How do you calculate the valency of an element from its electronic configuration?
Answer
  • The valency of an element is determined by the number of valence electrons present in the outermost shell of the atom.
  • For elements of group $1, 2, 13$ and $14$, the valency is equal to the number of valence electrons and for elements of group $15, 16, 17$ and $18,$ the valency is equal to $8$ minus number of valence electrons.
View full question & answer→
Question 241 Mark
Do they contain the same number of shells?
Answer
  • These elements contain the same number of shells $(2, K$ and $L).$
View full question & answer→
Question 251 Mark
Do these elements also contain the same number of valence electrons?
Answer
  • These elements do not contain the same number of valence electrons.
View full question & answer→
Question 261 Mark
If you look at the modern periodic table, you will find that the elements Li, Be, $B, C, N, O, F$ and Ne are present in the second period. Write down their electronic configurations.
Answer
Element $_3Li$ $_4Be$ $_5B$ $_6C$ $_7N$ $_8O$ $_9F$ $_{10}Ne$
Shell $K, L$ $K, L$ $K, L$ $K, L$ $K, L$ $K, L$ $K, L$ $K, L$
Electronic configuration $2, 1$ $2, 2$ $2, 3$ $2, 4$ $2, 5$ $2, 6$ $2, 7$ $2, 8$
View full question & answer→
Question 271 Mark
How many valence electrons are present in these three elements?
Answer
  • These three elements have one electron in their respective valence shell.
View full question & answer→
Question 281 Mark
What similarity do you find in their electronic configurations?
Answer
  • These elements possesses same number of electrons in their valence shell.
View full question & answer→
Question 291 Mark
Write down the electronic configuration of the first three elements of group $1.$
Answer
  • The electronic configuration of the first three elements are as follows :
Element $H$ Li Na
Shell $K$ $K,L$ $K,L,M$
Electronic configuration $1$ $2,1$ $2,8,1$
View full question & answer→
Question 301 Mark
Look at the group $1$ of the modern periodic table and name the elements present in it.
Answer
  • The names of the elements present in group $1$ are : hydrogen $(H)$, lithium $(Li)$, sodium $(Na)$, potassium $(K)$, rubidium $(Rb)$, cesium $(Cs)$ and francium $(Fr)$.
View full question & answer→
Question 311 Mark
Where do you think should hydrogen be placed in the modern periodic table?
Answer
  • Hydrogen should be placed in period $1$ and group $1$ in the modern periodic table, since it has atomic number one.
View full question & answer→
Question 321 Mark
Why do you think the noble gases are placed in a separate group?
Answer
  • Noble gases like helium (He), neon (Ne) and argon (Ar) are chemically very inert and are present in extremely low concentrations in our atmosphere.
  • Hence they are placed in a separate group.
View full question & answer→
Question 331 Mark
Besides gallium, which other elements have since been discovered that were left by Mendeleev in his periodic table?
Answer
  • Besides gallium, Mendeleev had left gaps for germanium and scandium in his periodic table.
View full question & answer→
Question 351 Mark
Which Sanskrit prefix was used by Mendeleev in the naming of elements which were not discovered at that time?
Answer
  • Eka
View full question & answer→
Question 361 Mark
Define term : Metalloids (Semi-metal)
Answer
  • Elements which possess intermediate properties of both metals and non-metals are called metalloids or semi-metals.
View full question & answer→
Question 371 Mark
Define term : Atomic radius
Answer
  • The distance between the centre of the nucleus and the outermost shell of an isolated atom is called atomic radius.
View full question & answer→
Question 381 Mark
Define term : Valency
Answer
The valency is the combining capacity of an atom of an element to acquire noble gas configuration.
View full question & answer→
Question 391 Mark
Define term : Periodic properties
Answer
  • Properties of the elements which are periodic function of their electronic configuration and are repeated after definite interval of atomic numbers.
OR
  • Properties which show the regular gradation in the same group (moving from top to bottom) or along a period (moving from left to right) are known as periodic properties.
View full question & answer→
Question 401 Mark
Define term : Isotopes
Answer
  • Atoms of the same element having same atomic number but different atomic masses are known as isotopes.
View full question & answer→
Question 421 Mark
Name the elements in the modern periodic table having lowest and highest atomic radii.
Answer
  • He and Fr
View full question & answer→
Question 471 Mark
Write the number of elements present in first, third and fourth period in the modern periodic table.
Answer
  • $2, 8, 18$
View full question & answer→
Generate Paper FreeAll periodic classification of elements topics
[1 Mark Questions] - Science STD 10 Questions - Vidyadip