If you get an intravenous injection containing 10 g of glucose, all glucose will enter the blood within few seconds and your blood glucose level will temporary rise by ~200 mg/dL.
If you take 10 g of glucose by mouth, the glucose will be dissolved and distributed within the stomach and small intestine and will be gradually absorbed into the blood, let's say within 30 minutes. In this time, some glucose will already move from the blood into the cells, so you will never have 10 g of additional glucose in the blood at a given time.
The actual blood glucose rise after ingestion of 10 g of glucose is not a fixed number, but a range that depends on several factors:
The gastrointestinal tract plays a major role in the regulation of
postprandial glucose profiles. Gastric emptying is a highly regulated
process, which normally ensures a limited and fairly constant delivery
of nutrients and glucose to the proximal gut. The subsequent digestion
and absorption of nutrients are associated with the release of a set
of hormones that feeds back to regulate subsequent gastric emptying
and regulates the release of insulin, resulting in downregulation of
hepatic glucose production and deposition of glucose in
insulin-sensitive tissues. These remarkable mechanisms normally keep
postprandial glucose excursions low, regardless of the load of glucose
ingested.** (Role of Gut in Glucose Homeostasis, Diabete Care, 2016)