उत्तरों सहित नर्सिंग प्रवेश परीक्षाओं के लिए रसायन विज्ञान वर्कशीट

What does the subscript 2 in H₂O tell you?

1. AEach molecule contains two hydrogen atoms
2. BThere are two water molecules
3. CEach molecule contains two oxygen atoms
4. DWater has a charge of 2

नमक के विलयन में नमक को क्या कहते हैं?

1. Aअवक्षेप
2. Bविलायक
3. Cविलेय
4. Dउत्प्रेरक

Which mixture is a suspension?

1. ASalt dissolved in water
2. BOxygen dissolved in water
3. CSand stirred into water
4. DSugar dissolved in water

Potassium forms K⁺ ions and sulfur forms S²⁻ ions. What is the name and formula of their compound?

1. APotassium sulfide, K₂S
2. BPotassium sulfide, KS₂
3. CPotassium sulfite, KS
4. DPotassium sulfate, K₂SO₄

Which gas forms when hydrochloric acid reacts with calcium carbonate?

1. AChlorine
2. BCarbon dioxide
3. CHydrogen
4. DOxygen

Radioactive iodine (iodine-131) is used to treat some thyroid conditions. Why does it reach the thyroid?

1. AIodine-131 is not radioactive inside the body
2. BRadiation is always drawn toward the head
3. CThe thyroid gland takes up iodine to make its hormones
4. DIodine is strongly attracted to the metal ions stored in the neck

Raising the temperature by 10 °C can roughly double the rate of many reactions. What is the main reason?

1. AThe reaction becomes more exothermic
2. BThe particles become larger and easier to hit
3. CMany more collisions have at least the activation energy
4. DThe activation energy itself is lowered by the extra heat

Why does a sodium ion (Na⁺) have almost the same mass as a sodium atom?

1. AThe only difference is one electron, which has a tiny mass
2. BThe ion gains a neutron that balances the loss
3. CIons and atoms always have exactly the same mass
4. DThe ion has one fewer proton, which has a tiny mass