kadar tindak balas

The reaction between zinc and hydrochloric acid is represented by the following chemical equation:

Tindakbalas antara zink dengan asid hidroklorik diwakili oleh persamaan kimia berikut

Zn + 2HCl → ZnCl₂ + H₂

Which of the following methods is the most suitable to determine the rate of the above reaction?

Antara kaedah berikut yang manakah paling sesuai untuk menentukan kadar bagi tindak balas di atas

• Determine the change in temperature of the solution with time Menentukan perubahan suhu larutan berkadar dengan masa

• Determine the change in the concentration of zinc chloride with time

  Menentukan perubahan kepekatan zink berkadar dengan masa

• Determine the volume of hydrogen gas given off with time

  Menentukan isipadu gas hidrogen yang dihasilkan berkadar dengan masa.

• Determine the change in the concentration of hydrochloric acid with time

  Menentukan perubahan kepekatan asid hidroklorik berkadar dengan masa,

The graph shows the volume of hydrogen gas produced against time for the reaction between zinc and sulphuric acid.

Graf menunjukkan isipadu gas hydrogen yang dibebaskan melawan masa bagi tindakbalas antara zink dan asid sulfurik..

The gradient of the graph decreases with time because

Kecerunan graf berkurang dengan masa kerana

• catalyst is not used.

  mangkin tidak digunakan

• volume of mixture decreases

  isipadu campuran berkurang

• temperature of reaction decreases

  suhu tindak balas berkurang

• concentration of sulphuric acid decreases

  kepekatan asid sulfurik berkurang

Diagram 3 shows the graph of the volume of gas produced against time for the reaction between calcium carbonate and hydrochloric acid.

Rajah 3 menunjukkan graf isipadu gas yang terhasil melawan masa untuk tindak balas antara kalsium karbonat dan asid hidroklorik.

The gradient of the curve decreases with time because

Kecerunan lengkung berkurang dengan masa kerana

• hydrochloric acid is a type of monoprotic acid

  asid hidroklorik adalah sejenis asid monobes

• temperature of reaction decreases

  suhu tindak balas berkurang

• volume of mixture decreases

  isipadu campuran berkurang

• concentration of hydrochloric acid decreases

  kepekatan asid hidroklorik berkurang

The time taken for 2 g of magnesium powder to react completely with excess hydrochloric acid is 5 minutes. What is the average rate of the reaction?

Masa yang diambil untuk 2 g serbuk magnesium bertindak balas lengkap dengan asid hidroklorik berlebihan ialah 5 minit.

Berapakah kadar purata bagi tindak balas ini?

• 0.4 g s^-1

• 0.4 g min^-1

• 2.5 g s^-1

• 2.5 g min^-1

Table 6 shows the volume of gas release at interval time of 30 seconds in an experiment to determine the rate of reaction .

Jadual 6 menunjukkan isipadu gas yang terbebas pada sela masa 30 saat dalam satu eksperimen untuk menentukan kadar tindak balas.

What is the average rate of reaction in the second minute?

Apakah kadar tindak balas purata dalam minit kedua?

• 0.06 cm³s^-1

• 0.12 cm³s^-1

• 0.37 cm³s^-1

• 7.00 cm³s^-1

Magnesium reacts with hydrochloric acid according to the equation below:

Magnesium bertindak balas dengan asid hidroklorik berdasarkan persamaan di bawah:

Mg (s) + 2HCl (aq) ----> MgCl₂ (aq) + H₂ (g)

Which of the following graphs of volume (V) of hydrogen gas against time (t) is correct?

Manakah antara graf isipadu(V) gas hydrogen melawan masa(t) berikut adalah betul?

• 
• 
• 
• 

Which of the following explain the meaning of effective collision?

Antara pernyataan berikut, yang manakah menjelaskan maksud perlanggaran berkesan?

• The collision where its energy is less than activation energy

  Tindak balas yang tenaganya kurang daripada tenaga pengaktifan

• The collision that has low energy

  Perlanggaran yang mempunyai tenaga yang rendah

• The collision that produces the product

  Perlanggaran yang menghasilkan hasil tindak balas

• The collision which take place before a reaction

  Perlanggaran yang berlaku sebelum sesuatu tindak balas

Which process has the lowest rate of reaction?

Proses manakah yang mempunyai kadar tindak balas yang paling rendah?

• Combustion

  Pembakaran

• Fermentation

  Penapaian

• Neutralisation

  Peneutralan

• Photosynthesis

  Fotosintesis

Which of the following factors does not affect the rate of a reaction?

Antara faktor-faktor berikut, yang manakah tidak mempengaruhi kadar sesuatu tindak balas?

• The presence of a catalyst

  Kehadiran mangkin.

• The concentration of the reactant

  Kepekatan bahan tindak balas

• The total surface area of the solid reactant

  Jumlah luas permukaan bahan tindak balas pepejal

• The mass of the solid reactant

  Jisim bahan tindak balas pepejal

The rate of chemical reaction can be determined by measuring

Kadar tindak balas boleh ditentukan dengan mengukur

I the volume of gas liberated per unit time.

isipadu gas dibebaskan per unit masa.

II the formation of precipitate per unit time.

pembentukan mendakan per unit masa.

III the change of colour per unit time.

perubahan warna per unit masa.

IV the change of the size of solid per unit time.

perubahan saiz pepejal per unit masa

• I and III only

  I dan III sahaja

• I,II and III only

  I,II dan III sahaja

• II,III and IV only

  II,III dan IV sahaja

• I,II,III and IV

  I,II III dan IV