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دوری جدول
6 سوالات: نویں جماعت کیمیا، جوابات اور وضاحت کے ساتھ۔
جوابی کنجی کے ساتھ قابلِ پرنٹ ورک شیٹ
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Elements in the same group of the periodic table have the same number of:
- 1 Valence electrons
- 2 Shells
- 3 Neutrons
- 4 Protons
جواب دیکھیں
درست جواب: Valence electrons
Elements in one group have the same number of valence electrons and so similar properties.
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Group IA elements are called:
- 1 Alkaline earth metals
- 2 Alkali metals
- 3 Halogens
- 4 Noble gases
جواب دیکھیں
درست جواب: Alkali metals
Group IA (lithium, sodium, potassium and so on) are the alkali metals.
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Which of these is a noble gas?
- 1 Oxygen
- 2 Neon
- 3 Sodium
- 4 Chlorine
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Moving from left to right across a period, the atomic size generally:
- 1 Stays the same
- 2 Increases
- 3 Doubles
- 4 Decreases
جواب دیکھیں
درست جواب: Decreases
The nuclear charge rises while the number of shells stays the same, so atoms get smaller.
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Halogens are found in group:
- 1 IIA
- 2 IA
- 3 VIIA
- 4 VIIIA
جواب دیکھیں
درست جواب: VIIA
Fluorine, chlorine, bromine and iodine are in group VIIA.
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Mendeleev arranged elements in order of increasing:
- 1 Melting point
- 2 Atomic mass
- 3 Density
- 4 Atomic number
جواب دیکھیں
درست جواب: Atomic mass
Mendeleev used atomic mass. The modern table uses atomic number.