Chemistry Random Retrieval Y12

Name the alkene CH₃CH(CH₃)CH=CHCH₃.

What is the H-C-H bond angle in ethene?

For which of the following equations is the value for standard enthalpy change equal to the standard enthalpy of formation of sodium chloride?

Hydrazine burns according to this equation: N₂H_4(g) + O_2(g) -> N_2(g) + 2H₂O_(l)

Calculate the standard enthalpy change for the combustion of hydrazine given that the standard enthalpy of formation of hydrazine is +51 kJmol^-1 and of water is -286 kJ mol^-1

Typically the molecular compounds of carbon with hydrogen:

(i) are insoluble in water

(ii) form solutions which do not conduct electricity

(iii) are soluble in liquid hydrocarbons

(iv) are denser than water

Which of these compounds consist of molecules which are linear?

(i) water

(ii) beryllium chloride

(iii) sulfur dioxide

(iv) carbon dioxide

A molecule of sulfur hexafluoride, SF₆ is:

Which of these statements is true of a metallic crystal?

(i) It consists of atoms strongly held together by metallic bonding.

(ii) It consists of a regular array of positive ions in a sea of negative electrons.

(iii) The crystal is held together by the attraction between positive metal ions and electrons.

(iv) The crystal is negatively charged.

Which of these compounds consists of a giant structure of ions?

Hydrogen is oxidised when it reacts with:

(i) oxygen to form water

(ii) nitrogen to form ammonia

(iii) chlorine to form hydrogen chloride

(iv) sodium to form sodium hydride

In the half equation: MnO₄^- _(aq) + 8H⁺_(aq) + ne^- -> Mn²⁺_(aq) + 4H₂O_(l) the value of n is:

Which of these reactions is an acid-base reaction?

Which of the following is not a typical property of most metals:

Which of these statements is true of a metallic crystal?

(i) It consists of atoms strongly held together by metallic bonding.

(ii) It consists of a regular array of positive ions in a sea of negative electrons.

(iii) The crystal is held together by the attraction between positive metal ions and electrons.

(iv) The crystal is negatively charged.

Steel and graphite are similar in that they both.

(i) conduct electricity

(ii) are dark grey/black when powdered

(iii) can have high tensile strength

(iv) are brittle

What is/are the bond angle(s) found in iodine trifluoride?

(i) 104.5^o

(ii) 120^o

(iii) 107^o

(iv) 90^o

In the formula of water, H-O-H, the lines represent:

(i) shared pairs of electrons

(ii) dative bonds

(iii) covalent bonds

(iv) hydrogen bonds

What is the molar mass of calcium hydroxide?

How many filled orbitals are there in the neon atom?

Using enthalpies of combustion Δ_cH, calculate the enthalpy change for the cracking of butane:

C₄H_10(g) => C₂H_6(g) + C₂H_4(g)

Select the data from the 'Selection of Enthalpies of Formation and Combustion' shown above.

If this question was generated from Random Retrieval, this data can also be found in TOOLS>Data Sheets.

The energy needed to atomise 1 mol of gaseous ethene, C₂H₄ is 2087 kJ mol^-1. Calculate the average bond enthalpy for a C-H bond given that the bond enthalpy for the C=C bond is +347 kJ mol^-1.

Hydrazine burns according to this equation: N₂H_4(g) + O_2(g) -> N_2(g) + 2H₂O_(l)

Calculate the standard enthalpy change for the combustion of hydrazine given that the standard enthalpy of formation of hydrazine is +51 kJmol^-1 and of water is -286 kJ mol^-1

The oxidising agent used to extract bromine from sea water in a displacement reaction is:

All the oxides of the metals Mg, Ca, Sr and Ba:

(i) are basic

(ii) consist of giant structures of ions

(iii) form nitrates when they react with dilute nitric acid

(iv) are freely soluble in water

Which of these comparative statements are true?

(i) a calcium atom is larger than a calcium ion

(ii) a calcium atom has a larger radius than a magnesium atom

(iii) calcium has a smaller first ionisation energy than magnesium

(iv) a calcium ion is smaller than a magnesium ion

A white crystalline solid gives a pale green colour in a flame. Adding silver nitrate to an acidified solution of the solid produces a white precipitate. The solid is:

What is the oxidation number of FLUORINE in

F₂O

What is the oxidation number of CHROMIUM in

Cr₂O₇^2-

What is the oxidation number of CARBON in

CH₄

Choose one of the following options:

There are two main peaks in the infra-red spectrum of carbon dioxide.

This shows that carbon dioxide molecules:

This procedure produces a white precipitate which dissolves easily in dilute ammonia solution: heating C₄H₉X for a few minutes with aqueous alkali, then acidifying the mixture with dilute nitric acid and adding silver nitrate. This shows that X is:

What are the conditions for converting 1,2-dichlorethane into ethane-1,2-diol?

Heating butan-1-ol with a mixture of sodium bromide and concentrated sulfuric acid produces 1-bromobutane. During the preparation the reaction mixture turns orange due to the formation of:

Which reagent can be used to convert butan-1-ol to but-1-ene?

Which of these alkenes will produce the largest %yield of 2-bromopentane when it is reacted with hydrogen bromide?

Name the alkene CH₃CH(CH₃)CH=CHCH₃.

Burning a hydrocarbon fuel such as methane gas in a limited supply of air is dangerous because under these conditions one of the products is: