What is the specific gravity of 92-octane gasoline?

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The specific gravity of one liter of 92-octane gasoline is 0.725 kilograms. Weight equals density multiplied by volume, and the density of 92-octane gasoline is 0.725g/ml, so one liter weighs 0.725 kilograms. However, the density of gasoline is not a fixed value, as it slightly varies with seasonal climate changes due to thermal expansion and contraction. Typically, the octane rating of gasoline to be used can be determined based on the engine's compression ratio. Vehicles with engine compression ratios between 8.6 and 9.9 should opt for 92-octane gasoline. Gasoline, known as 'Gasoline' in the US and 'Petrol' in the UK, appears as a transparent, flammable liquid with a distillation range of 30°C to 220°C. Its main components are C5 to C12 aliphatic hydrocarbons and cycloalkanes, along with a certain amount of aromatic hydrocarbons. Gasoline has a high octane rating for anti-knock combustion performance and is classified into grades such as 90, 93, 95, and 97 based on octane levels. It is produced by refining various gasoline components obtained from petroleum refining, including straight-run gasoline, catalytic cracking gasoline, and catalytic reforming gasoline, blended with high-octane components, primarily used as fuel for spark-ignition internal combustion engines in vehicles. The GB17930—2013 standard for automotive gasoline first specified density indicators, set at 720～775kg/m³ at 20°C, to further ensure relatively stable vehicle fuel economy. Considering the fifth-phase automotive gasoline, the reduction in octane number due to sulfur reduction and manganese prohibition, and the shortage of high-octane resources domestically, the standard adjusted the grades of automotive gasoline from 90, 93, and 97 to 89, 92, and 95, respectively, while adding 98-octane automotive gasoline. Generally, the higher the gasoline grade, the higher the octane number, and the better the anti-knock performance. 92-octane gasoline contains 92% isooctane and 8% n-heptane, while 95-octane gasoline contains 95% isooctane and 5% n-heptane. It is advised that using a higher octane gasoline in a vehicle designed for lower octane will not cause damage, but the increase in octane number can alter the fuel's ignition point, leading to delayed combustion in the engine. This means both the engine's power output and thermal efficiency will decrease, resulting in poorer performance. Using lower octane gasoline in a vehicle designed for higher octane can cause engine knocking. Because the octane number is too low, the gasoline's ignition point decreases and may ignite prematurely during the compression stroke. If combustion occurs before the spark plug fires during the compression stroke, resistance will arise during the upward stroke. This resistance makes the engine run very unstably. If the knocking is imperceptible, it only increases noise without significant damage to the engine. However, noticeable knocking indicates severe engine conditions, affecting not only driving stability but also causing abnormal wear on pistons and cylinders, potentially leading to cylinder scoring in severe cases.