Zadanie 9
What is the correct formula for ammonium sulfate? A. (NH4)2SO4 B. NH4SO4 C. NH4(SO4)2 D. (NH3)2SO4
Zapisujemy na Twoim urządzeniu to, bez czego serwis nie działa, np. zalogowanie. Plików analitycznych użyjemy tylko za Twoją zgodą. Szczegóły w polityce prywatności.
Baza zadań
Wybierz umiejętność, rok lub poziom trudności. Każde zadanie ma klucz i schemat punktowania.
Pokazujemy tylko poziomy, dla których mamy zadania.
Znaleziono 1061 zadań
What is the correct formula for ammonium sulfate? A. (NH4)2SO4 B. NH4SO4 C. NH4(SO4)2 D. (NH3)2SO4
Citric acid gives lemon juice its sharp taste. It dissolves very readily in water. Its structure is shown. Explain why citric acid is soluble in water, with reference to its structure.
What is the arrangement of the oxygen atoms around each silicon atom in the giant covalent structure of silicon dioxide? A. Linear B. Tetrahedral C. Trigonal planar D. Octahedral
Which bond is the most polar? A. C−S B. C−Br C. C−Cl D. C−O
Ethane forms a solid compound with water, ethane hydrate, which looks like ice but burns when ignited because the ice-like cages release ethane gas. In an idealized sample the formula is (C2H6)3(H2O)23 and the molar mass is…
Ethane is used as a fuel. Calculate its specific energy, in kJ g−1, using the enthalpy of combustion in section 14 and the atomic masses in section 7 of the data booklet.
What is the number of bonding pairs of electrons in propanedioic acid, HOOC−CH2−COOH? A. 8 B. 10 C. 12 D. 20
Bioethanol is made from the sugars that plants produce by photosynthesis. Write the balanced summary equation for photosynthesis, in which glucose is formed.
Natural gas, which is mainly methane, and coal, which is mainly carbon, are both burned in power stations. Outline why burning natural gas has a lower environmental impact than burning coal.
Which statement best explains why a block of copper can be hammered into a thin sheet without breaking? A. Cations in neighbouring layers repel one another, so they stay fixed in their positions B. Layers of cations can slide over one another because the…