ورقة عمل الكيمياء لامتحانات القبول في التمريض مع الإجابات

What does the coefficient 3 in "3H₂O" mean?

1. AEach water molecule has three oxygen atoms
2. BThere are three molecules (or moles) of water
3. CWater has a charge of 3
4. DEach molecule of water contains three hydrogen atoms

What is the SI unit of energy?

1. ANewton
2. BJoule
3. CKelvin
4. DWatt

Which element makes up the largest share of the human body by mass?

1. ANitrogen
2. BOxygen
3. CCarbon
4. DHydrogen

Why do group 1 metals such as sodium react so easily?

1. AThey have one outer electron that is easily lost
2. BThey easily gain one extra electron
3. CThey have a full outer shell of electrons
4. DTheir nuclei contain no neutrons

When diluting a concentrated acid, which method is safe?

1. AAdd the water quickly to the acid
2. BAdd the acid slowly to the water
3. CAdd the water slowly to the acid
4. DMix them in any order, as long as it is fast

أي خاصية نموذجية للمركّبات الأيونية مثل NaCl؟

1. Aدرجات انصهار عالية؛ وتوصل الكهرباء عند إذابتها
2. Bتوصيل الكهرباء وهي مواد صلبة جافة
3. Cدرجات انصهار منخفضة وتكون غازات في درجة حرارة الغرفة
4. Dكونها لينة وسهلة الانثناء كالفلزات

Hydrogen is usually placed at the top of group 1. Which statement about hydrogen is correct?

1. AIt is an alkali metal that is solid at room temperature
2. BIt has one valence electron like group 1 metals, but it is a nonmetal gas
3. CIt always forms H⁺ ions and never shares electrons
4. DIt has a full outer shell like the noble gases

أيون فيه 12 بروتونًا و10 إلكترونات. ما هو؟

1. ANa⁺
2. BMg²⁺
3. CNe
4. DMg²⁻