Chicago grains rose collectively Friday with hikes of the three major commodities of corn, wheat and soybean, amid better-than-expected exports, weakening U.S. dollar and bullish sentiments in energy and equity markets. The most active corn contract for December delivery closed at 6.4 U.S. dollars per bushel, up 1.75 U.S cents, or 0.27 percent. December wheat gained 4.75 cents, or 0.77 percent, to 6.2275 dollars per bushel. November soybean rose 13 cents, or one percent, to 12.7 dollars per bushel. Many market analyses pointed to the dollar\'s weakening in the day that buoyed up the grain market as a whole. The dollar index Friday declined 0.585 percent to around 76.6. Besides, U.S. Department of Agriculture (USDA) said the weekly exports of corn and wheat are better than traders\' expectation, giving additional push to the prices. According to a USDA report, for the week ended on Oct. 6, U.S. export sales for corn totaled 1.344 million metric tons, well above traders\' expectations and above one million for the third time in the past five weeks. The weekly exports for wheat came in at 500,600 metric tons, also higher than expected. Besides, the soybeans gained strength from bullish sentiments in energy market and settled higher for the fifth trading day in a row. New York crude oil rose 2.57 dollars to finish 86.8 dollars per barrel on Friday.